Basal

(a.) Relating to, or forming, the base.

Thesaurus Entries

ab ovo, aboriginal, basic, basilar, beginning, bottom, bottommost, central, constituent, constitutive, crucial, elemental, elementary, embryonic, essential, foundational, fundamental, generative, genetic, germinal, gut, in embryo, in ovo, lowermost, lowest, material, nethermost, of the essence, original, pregnant, primal, primary, primeval, primitive, primordial, pristine, protogenic, radical, rudimental, rudimentary, seminal, substantial, substantive, underlying, undermost