def,
when i used to smoke,way back when,it was always said that to take a third light off a match was unlucky.
apparently this came from ww1 trenches,a sniper would
1. see a light
2. train in on it
3. fire.
Def - coincidentally my girlfriend who's name really is Lucy thinks we're a match -
(the faint sound of the single faint handclap in a crowded theatre....)
Now you have competition in the "wish I hadn't mentioned it" stakes