Lentilist is a derogatory term for anyone with anti-car, anti-progress, anti-capitalist views. It particularly applies to filthy, scummy layabouts who spend their time protesting outside power stations instead of getting a fucking job, or middle-class socialist wankers with a guilt complex.
The term is derived from the assumption that people of this kind would rather eat lentils than a big juicy steak.
Also see: sandalist, yoghut weaver
Jane: "Oh, you shoud cycle to work, it's soooo much better for the environment"
Bob: "Fuck off you lentilist"