ulna

n. bone of the forearm found on the opposite side of the thumb (Anatomy)

The ulna (elbow bone) is a long bone, prismatic in form, placed at the medial side of the forearm, parallel with the radius.
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Ulna /ul·na/ pl. ul´nae [L.] the inner and larger bone of the forearm. ul·na n. pl. ul·nas or ul·nae The larger bone of the two bones of the [more]Ulna - Community and Resources

Noun
1. the inner and longer of the two bones of the human forearm
(synonym) elbow bone
(hypernym) arm bone
(part-holonym) forearm
(part-meronym) olecranon, olecranon process

n. ulna, bone of the forearm found on the opposite side of the thumb (Anatomy)