Common loanword for the squash, especially in food contexts. Often used in compound words like パンプキンパイ (pumpkin pie) or パンプキンスープ (pumpkin soup).
ハロウィンにはパンプキンを飾ります。
We decorate pumpkins for Halloween.
このパンプキンスープはとてもクリーミーだ。
This pumpkin soup is very creamy.