An archaic or dialectal form meaning to accost, approach, or come alongside something.
From Old French acoster, from a- (to) plus coste (side, coast). Related to modern 'coast' and 'accost,' showing how navigation terms influenced greeting vocabulary.
Sailors would 'acost' each other's ships by sailing alongside them, which is why the word came to mean addressing someone—you had to come near them first to talk to them.
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