under-lying (adjective) underlying: fundamental, latent
Sinonime: basal,
basic,
bottom, bottom-line,
cardinal,
concealed,
critical,
crucial,
elemental,
elementary,
essential,
hidden,
indispensable,
intrinsic, lurking,
necessary, needful, nitty-gritty, nub,
primary,
prime,
primitive,
radical,
root, substratal, veiled,
vitalAntonime: secondary