From Halopedia, the Halo wiki
In the 21st-century, some oceanic vessels were also known as yachts. Both the oceanic and starship versions are considered status symbols.
UNSC Prowlers are sometimes disguised as yachts by the Office of Naval Intelligence to avoid suspicion. The UNSC Circumference, the UNSC Apocalypso, the UNSC Lark, and the UNSC Applebee are all examples.
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