Etymology 1 
From Middle English brouken (“to use, enjoy”), from Old English brūcan (“to enjoy, brook, use, possess, partake of, spend”), from Proto-Germanic *brūkaną (“to enjoy, use”), from Proto-Indo-European *bʰrūg- (“to enjoy”). Cognate with Scots brook, brouk (“to use, enjoy”), West Frisian brûke (“to use”), Dutch bruiken (“to use”), German brauchen (“to need, require, use”), Norwegian bruke (“to use”), Latin fruor (“enjoy”). Related to fruit.
- (transitive, obsolete, except in Scots) To use; enjoy; have the full employment of.
- (transitive, obsolete) To earn; deserve.
- (transitive) To bear; endure; support; put up with; tolerate (usually used in the negative, with an abstract noun as object).
- I will not brook any disobedience.
- I will brook no refusal.
- 2005, Nicholas Ostler, Empires of the Word: A Language History of the World, Harper:
- Nevertheless, Garcilaso does claim that the Spaniards ‘who were unable to brook the length of the discourse, had left their places and fallen on the Indians’.
Derived terms 
- See under tolerate.
Etymology 2 
From Middle English, from Old English brōc (“brook, stream, torrent”), from Proto-Germanic *brōkaz (“stream”), from Proto-Indo-European *mrāǵ- (“silt, slime”). Cognate with Dutch broek (“marsh, swamp”), German Bruch (“marsh”), Ancient Greek βράγος (brágos, “shallows”) and Albanian bërrak (“swampy soil”).
brook (plural brooks)
- a body of running water smaller than a river; a small stream.
- (Sussex, Kent) a water meadow.
- (Sussex, Kent, in the plural) low, marshy ground.