swing by

WordReference Random House Unabridged Dictionary of American English © 2026

swing′ by′, 

1. Aerospace a trajectory that uses the gravitational field of one celestial body to alter the course of a spacecraft destined for another body.

• noun, nominal use of verb, verbal phrase swing by 1960–65, American.

Collins Concise English Dictionary © HarperCollins Publishers::

swing by verb

1. (preposition) to go somewhere to pay a visit