also: こうはん
Refers specifically to the deck of a vessel. The reading かんぱん is standard; こうはん is an older reading rarely used today.
船の甲板で朝日を見た。
I watched the sunrise from the ship's deck.
Let's go out on deck and feel the wind.
In the evening, I went out onto the deck and looked at the sea.
The sailors are walking around on the deck.
main deck
deck hand; deckhand