joke, jest, colloquial
諢 centers on informal, playful speech: joking, jesting, or using colloquial language. The meanings all involve words that are lighthearted or not serious.
諢 combines 言 (speech) with 軍, which likely contributes the sound. The character expresses joking or informal talk.
Words (言) from an army (軍) camp might be rough and full of jokes. Picture soldiers telling colloquial jokes to pass the time.
For コン, imagine a con artist telling jokes to trick people: con -> コン, and the speech radical 言 hints at the joking words.
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