before vowels oste-, word-forming element meaning "bone, bones," from Greek osteon "bone," from PIE root *ost- "bone."
Entries linking to osteo-
*ost-
Proto-Indo-European root meaning "bone."
It forms all or part of: osseous; ossicle; ossuary; ossifrage; ossify; osteo-; osteology; osteopathy; ostracism; ostracize; oyster; periosteum.
It is the hypothetical source of/evidence for its existence is provided by: Sanskrit asthi, Hittite hashtai-, Greek osteon "bone," Greek ostrakon "oyster shell," Avestan ascu- "shinbone," Latin os (genitive ossis) "bone," osseus "bony, of bone," Welsh asgwrn, Armenian oskr, Albanian asht "bone."
astragalus n.
1540s in botany, a large genus of plants that include the milkvetch, loco-weed and goat's thorn; 1560s in anatomy in reference to a type of bone, usually in or near the ankle. Historically these bones, especially those taken from deer, were used as a type of die for games and fortune telling. It is attested from 1560s in architecture as a type of molding. All senses are from Greek astragalos "neck vertebra; ankle bone; knuckle-bones (used as dice)," which generally is considered to be from the same root as osteon "a bone" (see osteo-), but Beekes says they are unrelated.