acquaintance
n. countablen. a person you know slightly, but who is not a close friend. You might see them at work or school, but you do not spend much free time together.
n. a person known to someone but not a close friend; a casual or formal associate. Typically used in the singular to denote a specific individual, or in the plural to refer to one's social circle.
He is just an acquaintance, not a friend.
She nodded to an acquaintance while waiting for the bus.
In a small town, every stranger is eventually reduced to an acquaintance through repeated, polite encounters.
From Middle English aqueyntaunce, from Anglo-Norman aquaintaunce, aqueintance, Old French acointance (“friendship, familiarity”), from Old French acointier (“to acquaint”). Compare French accointance. Morphologically acquaint + -ance.