bag, ballocks, balls, basket, beard, breasts, cervix, clitoris, cod, cods, cullions, family jewels, female organs, genitalia, genitals, gonads, labia, labia majora, labia minora, lingam, lips, male organs, matrix, meat, nuts, nymphae, ovary, penis, phallus, private parts, privates, privy parts, pubic hair, pudenda, reproductive organs, rocks, scrotum, secondary sex characteristic, sex organs, spermary, testes, testicles, uterus, vagina, venter, vulva, yoni
cause, origin, source, principle, element, occasioner, prime mover, primum mobile, vera causa, author, mainspring, agent, leaven, groundwork, foundation, spring, fountain, well, font, fountainhead, spring head, wellhead, fons et origo, genesis, descent, remote cause, influence, pivot, hinge, turning point, lever, crux, fulcrum, key, proximate cause, causa causans, straw that breaks the camel's back, ground, reason, reason why, why and wherefore, rationale, occasion, derivation, final cause, les dessous des cartes, undercurrents, rudiment, egg, germ, embryo, bud, root, radix radical, etymon, nucleus, seed, stem, stock, stirps, trunk, tap-root, gemmule, radicle, semen, sperm, nest, cradle, nursery, womb
, nidus, birthplace, hotbed, causality, causation, origination, production, caused, causal, original, primary, primitive, primordial, aboriginal, protogenal, radical, embryonic, embryotic, in embryo, in ovo, seminal, germinal, at the bottom of, connate, having a common origin, because, behind the scenes, causa latet vis est notissima, felix qui potuit rerum cognoscere causas.
interiority, inside, interior, interspace, subsoil, substratum, intrados, contents, substance, pith, marrow, backbone, heart, bosom, breast, abdomen, vitals, viscera, entrails, bowels, belly, intestines, guts, chitterings, womb
, lap, penetralia, recesses, innermost recesses, cave, interior, internal, inner, inside, inward, intraregarding, inmost, innermost, deep seated, gut, intestine, intestinal, inland, subcutaneous, abdominal, coeliac, endomorphic, interstitial, inwrought, inclosed, home, domestic, indoor, intramural, vernacular, endemic, internally, inwards, within, in, inly, here in, there in, where in, ab intra, withinside, in doors, within doors, at home, in the bosom of one's family.