Vacant a. : Deprived of contents; not filled; empty; as, a vacant room.

Vacant a. : Unengaged with business or care; unemployed; unoccupied; disengaged; free; as, vacant hours.

Vacant a. : Not filled or occupied by an incumbent, possessor, or officer; as, a vacant throne; a vacant parish.

Vacant a. : Empty of thought; thoughtless; not occupied with study or reflection; as, a vacant mind.

Vacant a. : Abandoned; having no heir, possessor, claimant, or occupier; as, a vacant estate.

Example:
I want to start a Vacant home cleaning service. Who generally hires those services? ?

Taxonomy
Merriam-Webster Online Dictionary, Dictionary, webster, Word Games, Webster Online Dictionary with audio pronunciations, Middle English, glossary, language, ESL, nt, adjective, Etymology, Anglo-French, Latin, vacans, present participle, vacare, 14th century.

Defination from the web:
vacant from the Merriam-Webster Online Dictionary with audio pronunciations, thesaurus, Word of the Day, and word games. ... Etymology: Middle English, from Anglo-French, from Latin vacant-, vacans, present participle of vacare to be empty, be free. Date: 14th century ...