Etymology
The noun is probably derived partly:
* from Middle English throu, throwe (“(chiefly in the plural) uterine contraction during the birth of a child; pain experienced while giving birth; suffering; a pain; emotional distress, anxiety”) [and other forms], perhaps from:
** Old English þrawu (rare), a variant of þrēa (“affliction, torment; disaster; oppression; a rebuke; severity; threat”), from Proto-West Germanic *þrau, from Proto-Germanic *þrawō (“longing; suffering”), from Proto-Indo-European *trewh₁-; and
** Old English þrōwian (“to endure, suffer”), from Proto-Germanic *þrōwijaną, probably from *þrawō (see above); and
** Old Norse þrá (“longing, yearning”), from Proto-Germanic *þrawō (see above); and
* from Middle English throuen (“to endure distress, suffer; to be ill, to have a fever; t