osteoblast

n. immature bone; germ cell of a bone

An osteoblast (from the Greek words for "bone" and "germ" or embryonic) is a mononucleate cell that is responsible for bone formation. Osteoblasts produce osteoid, which is composed mainly of Type I collagen. Osteoblasts are also responsible for mineralization of the osteoid matrix. Bone is a dynamic tissue that is constantly being reshaped by osteoblasts, which build bone, and osteoclasts, which resorb bone.
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Noun
1. a cell from which bone develops
(synonym) bone-forming cell
(hypernym) embryonic cell, formative cell

n. osteoblast, immature bone; bone cell

(n.)
One of the protoplasmic cells which occur in the osteogenetic layer of the periosteum, and from or around which the matrix of the bone is developed; an osteoplast.