shoe last; shoe stretcher
Refers to a shaped form used inside a shoe to maintain its shape or stretch it. Both 'shoe last' (for making shoes) and 'shoe stretcher' (for adjusting fit) are covered.
I use a shoe tree to maintain the shape of my leather shoes.
新しい靴がきついので、靴型で伸ばしている。
My new shoes are tight, so I'm stretching them with a shoe stretcher.
Compound of 靴 (kutsu, 'shoe') and 型 (kata, 'mold, form'). The reading くつがた follows standard rendaku voicing of the second element.