ダブル (daburu) means “double” | MotiTan Japanese Dictionary

More examples

朝食付きのダブルを予約しました。chō shoku tsu ki no da bu ru o yo yaku shi ma shi ta

I reserved a double room with breakfast included.

Refers to a hotel room for two people with one shared double bed.

ダブルルームdabururūmu: The full hotel term for a room for two people with one shared double bed.

二人用で、一つの大きなベッドを備えたホテルの部屋。futa ri yō de hito tsu no ō ki na be ddo o sona e ta ho te ru no heya

ダブル (daburu, "double") is a Japanese loanword from English double, which comes through Old French doble from Latin duplus, meaning "twofold".

In hotel English, a double room usually has one double bed, whereas a twin room usually has two separate beds.