Lowered oneself to do something considered beneath one's dignity; condescended to do something.
From Old French 'deignier', from Latin 'dignāre' (to deem worthy), related to 'dignus' (worthy). The meaning shifted to imply reluctant acceptance or condescension by the 14th century.
In Pride and Prejudice, Mr. Darcy finally deigns to dance with Elizabeth—the word perfectly captures that snobbish moment when someone acts like they're doing you a huge favor by treating you as an equal.
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