hammer; mallet (variant of 槌[chui2]); variant of 捶[chui2]

(bound form) vertebra

coccyx; tailbone

thoracic vertebra; the twelve thoracic vertebras behind the ribcage of humans and most mammals

lumbar vertebra

(anatomy) sacral vertebra; sacrum

cervical vertebra; the seven cervical vertebrae in the neck of humans and most mammals

invertebrate