Circuit (6)
'circuit' is the definition.
(synonyms)
This is the entire clue.
(Other definitions for lap that I've seen before include "Drink; lick" , "One round of the track" , "Once around the track" , "Circuit (of a race track)" , "One round of the course" .)
'circuit' is the definition.
(thesaurus)
This is all the clue.
(Other definitions for course that I've seen before include "Route for Crusoe" , "way" , "Part of a meal or a series of lessons" , "Prescribed number of lessons" , "Each separate part of meal" .)