Adjective basal has 3 senses
  1. radical, basal - especially of leaves; located at the base of a plant or stem; especially arising directly from the root or rootstock or a root-like stem; "basal placentation"; "radical leaves"
  2. basal, base - serving as or forming a base; "the painter applied a base coat followed by two finishing coats"
    Antonyms: incidental, incident (indirect, via basic)
  3. basal, basic, primary - of primary importance; "basic truths"
    Antonyms: inessential, unessential (indirect, via essential)
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