Poop deck and Shelter deck

Poop deck noun - An exposed partial weather deck on the stern superstructure of a ship.

Shelter deck and poop deck are semantically related. In some cases you can use "Shelter deck" instead a noun phrase "Poop deck".

Shelter deck noun - Upper deck having no overhead protection from the weather, but sheltering the deck below.

Poop deck and shelter deck are semantically related. Sometimes you can replace phrase "Poop deck" with "Shelter deck", this phrases are similar.