Periph´ery, n. Superficies; contour.

Peristal´tic, a. Denoting the peculiar motion of the intestines by which their contents are urged onward; the peristole.

Peritone´um, n. Thin smooth serous membrane lining the belly, and investing most of the contained organs.

Perone´al, a. Pertaining to the fibula.

Perone´us, a. for n. Name of a fibular muscle.

Per´vious, a. Open. Used synonymously with perforate in respect of the nostrils, but better restricted to the opposite of impervious or closed (as to an external opening).

Pes, n.; pl. pedes (which see). Foot. (96.)

Pes´sulus, n. Cross-bone of the syrinx; bony bar across lower end of windpipe, at point of forking into the bronchi.

Petro´sal, a. (Used substantively.) Same as petrous.

Pe´trous, a. Stony; hence, hard. The petrous bone is an element of the temporal bone.