sore loser who stubbornly refuses to admit being wrong
A yojijukugo describing someone who, even when clearly defeated, makes excuses or twists logic to avoid admitting fault. Rare and literary; not used in everyday conversation.
Even when he loses an argument, he's a sore loser who stubbornly refuses to admit he's wrong.
A common word for being a sore loser or making excuses after losing. 漱石枕流 is a rare, literary yojijukugo with a similar meaning but much more formal and classical.
Derived from a classical Chinese anecdote about a man who, after losing an argument, claimed he was using a stone to rinse his mouth and a stream as a pillow, twisting the original phrase '漱流枕石' (rinsing mouth with stream, using stone as pillow) to avoid admitting defeat. The exact historical derivation is uncertain, but the phrase is conventionally associated with stubborn refusal to admit error.