[a. Gr. χόριον outer membrane of fœtus.]
1. Anat. The outermost membrane enveloping the fœtus before birth.
1545. Raynold, Byrth Mankynde (1564), xxxiii. 32. The bastyng that is betweene the Matrix and Chorion.
1646. Sir T. Browne, Pseud. Ep., III. vi. In regard the cub comes forth involved in the Chorion, a thick and tough membrane.
1754–64. Smellie, Midwif., I. 114. The External coat of the Ovum is the membrane Chorion.
1836. Todd, Cycl. Anat., I. 116/1. The chorion of the ova [of the Reptilia] is generally thin or coriaceous, seldom calcified or hard.
1864. F. Hall, in Wilson’s trans. Vishṅu-puráṅa, I. 40. Meru was its amnion, and the other mountains were its chorion.
2. Bot. (See quot.)
1816. Keith, Phys. Bot., IV. viii. § 2. The Chorion, so named by Malpighi, is the soft and pulpy substance of the primitive nucleus of the seed.
3. Anat. The cutis vera or true skin; = CORIUM.
1831. R. Knox, Cloquet’s Anat., 333. They … terminate in the chorion of the skin.
1845. Todd & Bowman, Phys. Anat., I. 434. The chorion, or cutis, is tough.
† 4. = Choroid tunic. Obs.
1650. Bulwer, Anthropomet., 73. The thin membrane Chorion, the first that covereth the Optique sinew.
