"Achilles' Heel" - deadly weakness in spite of overall strength, which can actually or potentially lead to downfall

"Ad Hoc" - formed, arranged, or done for a particular purpose only

"Ad Hominem" - an argument rebutted by attacking the character, motive, or other attribute of the person making the argument rather than attacking the position of the argument itself
Example:
Person A: I think we should spend more money on environmental protection.
Person B: You just think that because you’re a stupid tree-hugger.

"Ad Nauseam" - to a sickening or disgusting degree; to go on endlessly; literally, to continue to seasickness

"Aficionado" (derived from a Spanish word) - an ardent devotee; a fan; an enthusiast

"An axe to grind" - an ulterior motive; to have a grievance with someone, especially where one feels the need to seek damaging retribution; to have a strong opinion about something, which you are often trying to persuade other people is correct; when you have a problem to work out with someone or you need to set someone straight

"Apple does not fall far from the tree" - refers to a father/mother and son/daughter not being different from one another or being identical in their actions and behaviors

"Arm's length relationship" - a relationship between two parties who are unrelated or strangers thus, each owes no special obligation to the other party

"Bask in one's glory" - taking great pride in one's achievement and wanting to feel good about one's self and what one has accomplished

"Basket Case" - someone in a completely hopeless or useless condition; a person who is suffering from extreme nervous strain; nervous wreck; someone or something that is incapable of functioning normally; one who is amputated

"Bat an eye" - to display a subtle emotional reaction like consternation, annoyance, sadness, or joy

"Between a rock and a hard place" - stuck in a situation where one is faced with two equally difficult alternatives

"Beyond (or Above) reproach" - blameless; faultless; perfect; no such criticism can be made; unable to be criticized

"Bird in the hand beats two in the bush" - it is better to have something that is certain or keep what you have rather than risk losing it by trying to get something better where you might lose everything; it's better to have a lesser but certain advantage than the possibility of a greater one that may come to nothing

"Bite one's tongue" - to stop oneself from saying something (often something potentially inappropriate, hurtful, or offensive); making a desperate effort to avoid saying something

"Bite the bullet" - to accept something difficult and try to live with it; to endure a painful or otherwise unpleasant situation that is seen as unavoidable

"Bites the dust" - to fail or to stop existing; to die

"Blanket statement" - a vague and noncommittal statement asserting a premise without providing evidence; a statement that attempts to cover all situations (like a blanket) but is actually not true in all situations; a rule that affects everyone or includes all possible cases

"Born with a silver spoon in (your/one's) mouth" - born into wealth and privilege; someone who is lucky or inherently rich

"Broad brush" - an approach, strategy, or solution that deals with a problem in a general way rather than concentrating on the details; to describe or characterize something in very general, vague, or broad terms while ignoring or neglecting to include specific details

"Bug a boo" - something that causes fear or worry; someone who is clingy; stalker; an annoying person

"Bury/Stick head in the sand" - refuse to confront or acknowledge a problem; to hide from obvious signs of danger; to ignore unwanted news or events in the hope that they will go away; belief originated from how an ostrich buries its head when it is in danger

"Bury the hatchet" - to make peace; end a quarrel or conflict and become friendly; The phrase comes from the practice among native American and Canadian tribes literally to bury a war axe at the end of hostilities

"Call off the dogs" - to stop criticizing, attacking, or behaving aggressively toward someone; discouraging others from criticizing or attacking another person

"Can't see the forest for the trees" - one needs to step back from the tree in order to see the entire forest; an expression used of someone who is too involved in the details of a problem to look at the situation as a whole; to be so concerned with specifics or details that the larger problem, situation, or point is missed; if you look at things one at a time, you might not realize that a branch of separate "trees" go together to make a "forest"

"Capiche" (derived from the Italian word "capisci") - another way of saying, "Do you understand?"; a reply saying, "I understand."

"Cardinal Rules" - a substantial rule in place for a certain situation or organization; it must not be broken at anytime; a fundamental rule upon which other matters hinge

"Carpe Diem" - enjoy the pleasures of the moment without concern for the future; take full advantage of present opportunities; seize the day

"Catcall/Catcalling" - make a whistle, shout, or comment of a sexual nature to a woman passing by; the act of shouting harassing and often sexually suggestive, threatening, or derisive comments at someone publicly

"Catch 22" - a frustrating situation in which one is trapped by contradictory regulations or conditions; any illogical or paradoxical problem or situation; dilemma; a condition or regulation; preventing the resolution of a problem or situation

"Catch/Caught wind of" - to become aware of something, especially something being kept secret

"Changing of the guard" - a situation in which there is a dramatic or big change; a time in which new people are replacing other people in positions of importance; any situation in which an individual or group charged with a task or responsibilities in an organization is replaced by another individual or group

"Checkered Past" - bad history of someone due to unreputable actions from the previous years; somebody who has an inconsistent past, and characterized by periods of trouble or controversy as well as periods of success; a person whose track record that is up and down and all over the place

"Chink in the armor" - an area of vulnerability; a figurative term for a one's weakness, largest flaw, or their prevention of success

"Chip on the shoulder" - someone who has a self-righteous feeling of inferiority; holding a grudge or grievance that readily provokes disputation; refers to when someone refuses to do what they are told because the person in charge is incompetent

"Chomping at the bit" - to be impatient or eager for something to happen or over some delay; being so stupidly excited about something that you grind your teeth, like a racehorse does when being ridden

"Cookie cutter model" - marked by sameness and a lack of originality; a term used for some humans as in expecting all humans to be identical in habits, clothing, etc.

"Cookie cutter model" - marked by sameness and a lack of originality; a term used for some humans as in expecting all humans to be identical in habits, clothing, etc.

"Cop Out" - an excuse created to not doing something or shirk responsibility; something that avoids dealing with a problem in an appropriate way

"Cut and dry" - prearranged, unchangeable, and dull; fixed; determined beforehand; usual and uninteresting

"Cut corners" - to do something in the easiest, cheapest or quickest way, often by ignoring rules or leaving something out at the expense of high standards; to skip certain steps in order to do something fast to the detriment of the finished product or end result; taking a shortcut

"Day of reckoning" - a time when the effects of one's past mistakes or misdeeds catch up with them; the time when one is called to account for one's actions, to pay one's debts, or to fulfill one's promises or obligations

"Debbie Downer" - a someone who says something terribly depressing and destroys the positive atmosphere; person with an incessant need to bring down the collective mood and general ambience of a group; one who adds bad news and negative feelings to a gathering

"Delusion of Grandeur" - a false impression of one's own importance

"Devil's advocate" - a person who expresses a contentious opinion in order to provoke debate or test the strength of the opposing arguments; one who argues against a cause or a position, not as a committed opponent but simply for the sake of argument or to determine the validity of the cause or position

"Devils in the details" - when you do not concentrate on the details of something you may run into unexpected problems; small things in plans and schemes that are often overlooked can cause serious problems later on

"Die a little (inside)" - having a part of your soul (or heart) stripped away without any warning

"Ditto" - another of the same; duplicate; used to avoid repeating or to confirm agreement with an immediately preceding sentence; to copy; repeat

"Divide and conquer" - to make a group of people disagree and fight with one another so that they will not join together against one

"Dog days of summer" - the most sultry period of summer, from about July 3 to Aug. 11; Sirius, the “dog star,” rises and sets with the sun in the summer. During late July Sirius is in conjunction with the sun, and the ancients believed that it's heat added to the heat of the sun, creating a stretch of hot and sultry weather. They named this period of time, from 20 days before the conjunction to 20 days after, “dog days” after the dog star

"Draw a line in the sand" - to create or declare an artificial boundary and imply that crossing it will cause trouble; lay down a challenge; to provide a test of commitment; indicate the threshold or level above which something will become unacceptable or will provoke a response; to create a boundary and imply or declare that its crossing will provoke a negative response

"Draw first blood" - the initial advantage gained by one side in any game, contest or competition; the first damage or reverse inflicted on an opponent in a conflict

"Dribs and drabs" - in small portions; bit by bit; in small scattered or sporadic amounts

"Dumpster Fire" - a complete disaster or chaotic situation; something very difficult that nobody wants to deal with

"Dunning–Kruger Effect" - a cognitive bias wherein people of low ability suffer from illusory superiority, mistakenly assessing their cognitive ability as greater than it is; people fail to adequately assess their level of competence or their incompetence

"Ebb and Flow" - a decline and increase, constant fluctuations; to decrease and then increase, as with tides; a decrease followed by an increase, as with tides; the give-and-take of any relationship. Taking the good with the bad; a condition or rhythm of alternate forward and backward movement or of alternate decline and renewed advance

"Echo chamber" - an insular communication space where everyone agrees with the information and no outside input is allowed; people who agree with you

"Embarrassment of riches" - an overabundance of something, or too much of a good thing; having more of something than one needs and makes it difficult for one to choose

"Epley Maneuver" - a repositioning maneuver used by medical professionals to treat one common cause of vertigo, benign paroxysmal positional vertigo of the posterior or anterior canals of the ear

"Eye in the sky" - any person who watches a situation from above; an overhead surveillance camera