lunt (LUNT) - (Scot.) n., a slow-burning match or fuse; smoke esp. from a tobacco pipe. v., to produce or emit smoke.
This dates back to at least the 1540s, and comes from Dutch lont, match/fuse, and is akin to Middle Low German lunte, match/wick, but where it comes from before that I can't find.
See? A four-letter word.