godan verb (-su), transitive verb
wear out; wear until threadbare
Used for footwear or lower-body clothing that becomes worn out through long use. The verb implies the item has been used so much it is no longer in good condition.
お気に入りのスニーカーを履き古して、穴が開いてしまった。
I wore out my favorite sneakers and they got holes in them.
He has been wearing those jeans for years until they are threadbare.