(Anatomy & Zoology)a very small bone, especially one of those in the middle ear (剖,动)小骨(尤指听小骨) ■(Zoology)a small piece of calcified material forming part of the skeleton of an invertebrate animal such as an echinoderm (动)小骨片
语源
late 16th cent.: from Latin ossiculum, diminutive of os 'bone'