舌先三寸
shita.saki.san.zun

Literally: tongue – before/tip – three – sun (pronounced like “soon”; a unit of measurement approximately equal to 1.19 in. or 3.03 cm)

Alternately: Glib lies. Deceptive eloquence or flattery. The ability to control or influence people with words – false or hollow words, specifically, rather than genuinely persuasive argument.

Notes: Apparently many native speakers of Japanese replace 舌 with 口 (kuchi), but this is still generally considered an error by scholars.

This four-character compound doesn’t mean what I thought it meant when I first encountered it. The problem for me was the English expression “on the tip of my tongue,” meaning a word or phrase that you know and want to use but can’t quite remember at the moment. Keep in mind, though, that three sun is about 9cm (three and a half inches), a significant percentage of the visible portion of the tongue.

There’s got to be an amazing story behind this one, but it seems to be relatively obscure and none of my sources treated its origins beyond mentioning the Shǐjì.

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