noun
hip flask
A small, flat flask for carrying liquor, often slipped into a pocket. The Japanese term is a direct loan from English 'skittle', though the English word originally referred to a different object.
from English skittle
彼はジャケットの内ポケットにスキットルを忍ばせている。
He keeps a hip flask tucked in the inside pocket of his jacket.
スキットルにウイスキーを入れて持っていく。
I fill a hip flask with whiskey and take it along.