Antonyms for supplemental

noun:

imperative, nonreciprocal, integral, prime, needed, primary, fundamental, principal, vital, necessary, all-important, main, subtractive, requisite, needful, required, basic, chief, indispensable, essential.

Paraphrases for Supplemental:

• Adjective :
  accessory, add-in, add-on, added, additional, additonal, adjunct, adjunctive, adjuvant, after-care, aggregate, allied, alternative, annex, annexe, appendix, assistive, associate, auxiliary, back-up, complement, complementary, complements, complimentary, divisional, drop-in, excess, expanded, extended, extra, fall-back, Flanking, follow-on, follow-up, further, incidental, increased, incremental, interrelated, marginal, more, mutually-reinforcing, non-core, occupational, off-farm, postretirement, reinforcing, remaining, remedial, replenishment, residual, residuary, schedule, secondary, separate, shim, spare, special, standby, subsequent, SUBVENTED, super, supplement, supplementary, Supplemented, Supplementing, supporting, supportive, top-up, value-added.
• Noun, singular or mass :
  add-in, add-on, addition, additional, additionality, adjunct, adjunctive, augmentation, back-up, companion, complement, complementarity, complementary, complementation, complements, compliment, complimentary, continuation, employee, equivalent, excess, extension, extra, fall-back, Flanking, follow-up, grace, incremental, interlocking, non-core, overtime, replacement, replenishment, spokesman, supplement, supplementary, supplementation, Supplementing, top-up, trailer.
• Proper noun, singular :
  accessory, add-in, add-on, added, additional, adjunct, adjunctive, companion, complement, complementarity, complementary, complimentary, continuation, extended, extension, extra, follow-up, further, incremental, more, overtime, panels, special, supplement, supplementary, supplementation, Supplementing, supplements, supporting, supportive, surcharges, top-up.
• Verb, 3rd person singular present :
  additional.