the.com/occupant

means The person who is currently in or holding a space — a seat, a room, a house, an office — regardless of who owns it or how long they'll stay.

from From Latin occupare, 'to seize, take possession of' — built from ob- ('over, toward') plus capere ('to take, grab'). The same root gives us 'occupy' and 'occupation.' So an occupant is, etymologically, someone who has simply grabbed the spot — a word with a faint echo of conquest now used for whoever's merely sitting in 4B.