プログレッシブ和英中辞典(第4版)の解説
せすじ【背筋】
the muscles along the spine
背筋が痛む
I have a pain in my back.
背筋を伸ばした
He straightened his back.
気味の悪い話を聞いて背筋が寒くなった
A 「cold shiver [chill] ran down my spine when I heard the weird story.／The weird story sent a chill down [up] my spine.