Word Study
bursa
CIDE DICTIONARY
bursa, n. [L. See Burse.].
Any sac or saclike cavity; especially, one of the synovial sacs, or small spaces, often lined with synovial membrane, interposed between tendons and bony prominences. [1913 Webster]
OXFORD DICTIONARY
bursa, n. (pl. bursae or bursas) Anat. a fluid-filled sac or saclike cavity to lessen friction.
Derivative
bursal adj.
Etymology
med.L = bag: cf. PURSE
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