near the knuckle

Prepositional phrase

Britain informal

(Britain, informal) Risqué, sexual, suggestive of impropriety.

Japanese Meaning

性的なニュアンスを含み、いやらしさや不適切な印象を与える表現

Be careful with that joke — it's a bit near the knuckle for this audience.

その冗談には気をつけてください。この客層には少し性的に際どいです。

Sense（1）

(Britain, informal) Risqué, sexual, suggestive of impropriety.

So near the knuckle, I wonder they got past the censor.