Able to be tolerated or endured; acceptable or bearable.
From brook (to tolerate) + the suffix '-able' (capable of being). Brook comes from Old English 'brucan' (to use, enjoy).
Brook is one of English's most forgotten verbs—it means 'tolerate'—so brookable means 'tolerable.' But 'brook' is usually used negatively: 'I will not brook any nonsense,' which makes it sound like an old-fashioned parent.
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