A vehicle or item of furniture that has a specified seating capacity(noun)
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Use "seater" in a sentence
"I found out real quick that while the 1 seater is easier to put up, I would much rather sit in the 2."
"As I cannot believe that scaling up the lessons of Apollo to a six-seater is that impossible, I have to assume that there is a certain degree of 'spin' at work here."
"This sixty-seater is aimed squarely at the local Venetians, with lots of traditional recipes, particularly the fishy ones."