So ridiculous, absurd, or inadequate that it seems funny or deserving of mockery.
From 'laugh' (from Old English 'hlæhhan') + '-able' (capable of being). This combination became standard in English to describe things worthy of ridicule.
When something is laughable, you're not laughing with it—you're laughing at it, which is why the word implies something is absurdly bad or weak rather than genuinely funny.
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