synchondrosis UK /ˌsɪŋ.kɒnˈdɹəʊ.sɪs/US /ˌsɪnˌkɑnˈdɹoʊ.sɪs/ noun1 •A form of only slightly moveable articulation between bones joined by hyaline cartilage, as in the spinal vertebrae. formssynchondroses