Synonyms for Adjacent (same or very similar meaning)
WordNet sense 1 (having a common boundary or edge; touching):
adjoining, conterminous, contiguous, abutting, neighboring
WordNet sense 2 (joined or linked together):
connected
WordNet sense 3 (nearest in space or position; immediately adjoining without intervening space):
next, side by side
WordNet sense 4 (at or within a short distance in space or time or having elements near each other):
close
WordNet sense 5 (not far distant in time or space or degree or circumstances):
near
From the ODE community, based on WordNet
add/edit