in advance is an adjective and adverb meaning "situated ahead or going before". It carries 2 recorded senses.
ahead of time; in anticipation
“when you pay ahead (or in advance) you receive a discount”
“We like to plan ahead”
“should have made reservations beforehand”
Definitions, synonyms and semantic relations for in advance come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.