Why some British designers called carriers three-deck cruisers

Did navies use cruiser-style labels for aircraft carriers?

Yes. British designers used the term three-deck cruiser, and naval architects report that it persisted informally longer than official documents imply.

Early carrier language evolved while navies were still deciding how aviation ships related to cruiser and capital-ship traditions. Surviving formal records differ from the professional usage reported by naval architects, who say the older label persisted informally.