N. 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

V. be the cause of, originate, give origin to, give rise, to, give occasion to, cause, occasion, sow the seeds of, kindle, suscitate, bring on, bring to bring pass, bring about, produce, create, set up, set afloat, set on foot, found, broach, institute, lay the foundation of, lie at the root of, procure, induce, draw down, open the door to, superinduce, evoke, entail, operate, elicit, provoke, conduce to, contribute, have a hand in the pie, have a finger in the pie, determine, decide, turn the scale, have a common origin, derive its origin

Adj. 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

Adv. because, behind the scenes

Phr. causa latet vis est notissima, felix qui potuit rerum cognoscere causas