"existing from birth," 1796, from Latin congenitus "born or produced together," from assimilated form of com "together, with" (see con-) + genitus, past participle of gignere "to beget" (from PIE root *gene- "give birth, beget"). This sense formerly belonged to congenial (which is attested from 1660s with this meaning). Related: Congenitally.

1570s, "to hurt, damage;" 1580s, "fail become deficient" (senses now obsolete); 1590s, "to desert, revolt," from Latin defectus, past participle of deficere "to fail, desert," from de "down, away" (see de-) + combining form of facere "to do, make" (from PIE root *dhe- "to set, put"). Related: Defected; defecting.

early 15c., "want or lack of anything," especially lack of something essential to perfection or completeness, from Old French defect and directly from Latin defectus "failure, revolt, falling away," noun use of past participle of deficere "to fail, desert," from de "down, away" (see de-) + combining form of facere "to do, make" (from PIE root *dhe- "to set, put").

"defect of sustenance from imperfect assimilation of food," 1843, from mal- + nutrition.

congenital disease of the epidermis, 1815, coined in Modern Latin (1801); see ichthyo- + -osis. So called for the hard dry scales and plates which form on the skin. 

also mooncalf, "abortive, shapeless, fleshy mass," 1560s, attributed to the influence of the moon; from moon (n.) + calf (n.1). In later 16c., "deformed creature, monster;" from 1620s as "congenital idiot."