Behavior that is intended to seem humble but comes across as fake and unflattering.(noun)
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Use "false modesty" in a sentence
"As you know, I've no false modesty about my ability to arouse base passion in the lewder sort of female (and some not so lewd, neither, until I taught 'em how), but I've never deluded myself that I'm the kind who inspires deep lasting affection — except in Elspeth, thank God, but she's an emotional half-wit."