APG:

11.  *p e: r- „verführen, verderben", 
in ags. a:-pœ:ran, 
for-pœ:ran, 
neben a:-fæ:ran „schrecken" 
und seiner Sippe (hd. Gefahr).


FGB:

Peireach, -righe, a., furious.
Peireadh, g. -ridh, -rthe, pl. -ridheacha, m., a squall, suffering, etc.; 
a anam ag cur a peiridhcaca de, his soul (in Purgatory) getting through its sufferings; 
al. pearadh.
Peiriacal, -ail, m., peril, danger, risk; agony, severe sickness; 
p. báis, danger of death; 
i bpéin a bpeiriacail, at their peril; 
ar do ph., at your peril; 
al. -ail, gnly. priacail, g. -ala, -clach, f.; Lat. periculum.
Peiriaclach, -aighe,.a., dangerous, risky, anxious, troubled, sore, painful; 
uair ph. an bháis, the dread hour of death; 
tá mo mhéar p. go leor, my finger is pretty sore; 
al. priaclach.
Peiriughadh, m., act of panting, being out of breath, fussing; excitement, 
rage, a squall or perry; 
ar p., in an excited state, on tenterhooks; 
bhí sé ar p. chugham, he was furious with me; 
pith.-readh, peithriughadh (Om.); 
cf. piorra, peireadh.