1.
spine, back, line of the back
The line running down the center of the back, or the back as it relates to posture. Often used when talking about straightening or correcting one's posture.
背筋を伸ばして座る。
Sit up straight.
あの怖い話を聞いて背筋が凍った。
That scary story sent chills down my spine.
面接では背筋をまっすぐにして、相手の目を見て話すことが大切だ。
In job interviews, it's important to sit up straight and speak while looking the other person in the eye.
READING NOTE:
When referring to posture and the line of the back, the reading is せすじ. When referring specifically to the back muscles (as in exercise/anatomy), it is read as はいきん. The two readings represent different meanings.
COMMON COLLOCATIONS:
- 背筋を伸ばす (straighten one's back, sit/stand up straight)
- 背筋が凍る (a chill runs down one's spine)
- 背筋がぞっとする (feel a shiver down one's spine)
- 背筋がピンとしている (have good posture)
SIMILAR WORDS:
- 姿勢: posture (more general, can be abstract — attitude/stance)
- 背骨: spine, backbone (the actual bones of the spinal column)