seatmate

[ seet-meyt ]
/ ˈsitˌmeɪt /
|

noun

a person who shares a seat or occupies the seat next to oneself on a bus, plane, etc.

Origin of seatmate

An Americanism dating back to 1855–60; seat + mate1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

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