noun
coccyx; tailbone
Anatomical term for the small triangular bone at the base of the spine.
See also: 尾骨
転んで尾てい骨を打った。
I fell and hit my tailbone.
Standard kanji spelling; 尾骶骨 is a less common variant.
Variant spelling using 骶; less common than 尾てい骨.
尾骨 is a more formal medical term for coccyx; 尾てい骨 is the common everyday word.
Compound of 尾 (tail) + てい (骶, sacrum) + 骨 (bone). The てい is from 骶骨 (sacrum), so the whole means 'tail-sacrum bone'.