pain 
(pān)
(pān)n.
1.
a. An unpleasant feeling occurring as a result of injury or disease, usually localized in some part of the body: felt pains in his chest.
b. Bodily suffering characterized by such feelings: drugs to treat pain.
2.
a. Mental or emotional suffering; distress.
b. An instance of this: the pains of humiliation.
3. pains The pangs of childbirth.
4. pains Great care or effort: taking pains with one's work.
5. Informal A source of annoyance; a nuisance: Stuffing all these envelopes is a real pain.
tr.v. pained, pain·ing, pains
Idiom: 1. To cause physical pain to; hurt: My feet really pained me after the hike.
2. To cause mental or emotional distress to: "It pained him to remember every little thing about her" (John Irving).
on/under pain of
Subject to the penalty of (a specified punishment, such as death).
[Middle English, from Old French peine, from Latin poena, penalty, pain, from Greek poinē, penalty; see kwei-1 in the Appendix of Indo-European roots.]
Synonyms: pain, ache, pang, stitch, throe, twinge
These nouns denote a sensation of severe physical discomfort: abdominal pain; aches in my leg; the pangs of a cramped muscle; a stitch in my side; the throes of dying; a twinge of arthritis.
These nouns denote a sensation of severe physical discomfort: abdominal pain; aches in my leg; the pangs of a cramped muscle; a stitch in my side; the throes of dying; a twinge of arthritis.