Definition of gaffers:
(n) :
(film) A chief lighting technician for a motion-picture or television production.
(n) :
(UK, informal) The leader of a group or team, such as a boss, foreman, coach, or publican.
(n) :
Someone aboard a boat whose duty is to gaff a (large) fish once the angler has reeled it in.
(n) :
A glassblower.
(n) :
A sailor.
(n) :
(colloquial) An old person, usually a man.