ab ovo, basal, basic, basilar, between the lines, bottom, cardinal, constituent, constitutive, covert, critical, crucial, cryptic, delitescent, dormant, elemental, elementary, esoteric, essential, foundational, fundamental, gut, hibernating, hidden, indispensable, latent, lurking, material, muffled, mystic, necessary, needful, obfuscated, obscured, occult, of the essence, original, possible, potential, primal, primary, primitive, radical, rudimentary, sleeping, submerged, substantial, substantive, under the surface, unmanifested, veiled, virtual, vital