Constrain means to force or compel.
Constrain is a verb.
Synonyms: compel, strong arm, urge, coerce, drive, force, pressure.
Antonyms: plead, request, ask, implore.
My conscience constrained me to apologize.
Mr.Ravi couldn't constrain his impulse to gloat; he danced around the room chanting, "where is the book? where is the book?"
Durga was constrained to admit that she had dismantled her ex-boyfriends motorcycle.