Definition of "lav"

lav

/læv/

noun
plural lavs
1. (British, slang) Clipping of lavatory.
  Quotations
  If you had too much slap on when you went out . . your mates say too much slap on your ecaf. Yeah. Oh really girl? Yes . . Go in the lavs here and have a look.
  Quoted in 2006, Matt Houlbrook, Queer London (page 151)
2. (film, informal) Clipping of lavalier.