Green’s Dictionary of Slang

filter n.

[cigarette imagery: a worthless cigarette would have all filter and no tobacco]

In phrases

all filter (adj.)

(US teen) worthless, lacking in substance.

Show quotations
[US]Baltimore Sun (MD) Sun. Mag. 4 Dec. 9/1: ‘Am I out to lunch?’ she asked a straight man. ‘Am I all filter? How did I get into this Vancouver bit?’.