phrase/də la fɛs ɡoʃ/
Distant and unspecified, indirect, dubious, or notional, in speaking of a family relationship, ethnic heritage, etc.; shirttail (relative).
“J'ai juste ma famille immédiate dans ma vie; j'ai une tonne de cousins de la fesse gauche mais je ne les connais pratiquement pas.” — I only have my immediate family in my life; I have a ton of distant cousins but I barely know them at all.
Literally, “of the left buttock”.