noun
height of the neck; neckline height
Refers to the vertical dimension of a garment's neck or collar area, often in tailoring or clothing descriptions.
このシャツは襟腰が高すぎて、首がきつく感じる。
The neck of this shirt is too high, and it feels tight around my neck.
スーツの襟腰を少し低く直してもらえますか。
Could you adjust the suit's collar height a little lower?