Pl. fræna, frena. [L. frēnum, frænum, bridle.]
1. Anat. A small ligament or membranous fold which bridles or restrains the motion of the organ to which it is attached; e.g., that of the tongue.
1741. Monro, Anat. (ed. 3), 147. The Frænum of the Tongue.
1754–64. [see FOURCHETTE].
1807–26. S. Cooper, First Lines Surg. (ed. 5), 382. In persons born dumb, the state of the frænum should always be examined.
1872. Cohen, Dis. Throat, 51. This is the glosso-epiglottic fold, or posterior frænum of the tongue, or frænum of the epiglottis.
2. (See quot. 1859.)
1859. Darwin, Orig. Spec., vi. (1878), 148. Pedunculated cirripedes have two minute folds of skin, called by me the ovigenous frena, which serve, through the means of a sticky secretion, to retain the eggs until they are hatched within the sack.
1877. Huxley, Anat. Inv. Anim., vi. 295. It may be doubted if the ovigerous fræna of Lepas exert, as they have been supposed to do, a branchial function.
