Don't be fooled by his rough exterior — he has a heart of gold.
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Colloquial. Often used self-deprecatingly to claim humility ('I'm just a country bumpkin') or affectionately about a brusque-but-kind friend. Calling someone else a 大老粗 to their face is borderline rude — only safe between close friends or when the speaker is clearly being warm. The tone is closer to 'rough diamond' than 'lout'.
memory
Literally 'big-old-coarse' — 大 (big) + 老 (old, here as an intensifier of character) + 粗 (rough/coarse). Picture a brawny, uneducated farmer with calloused hands and a generous laugh.
