ichidan verb
cut and insert; cut in
Used when cutting something and inserting it into another object, such as a slot or opening. Often implies a precise or careful action.
板に溝を切って、そこにガラスを切り入れる。
Cut a groove in the board and insert the glass into it.
彼は生地に切り込みを入
He made a slit in the fabric and inserted another piece of cloth into it.