basal
     adj 1: 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" [syn: {radical}] [ant: {cauline}]
     2: serving as or forming a base; "the painter applied a base
        coat followed by two finishing coats" [syn: {base}]
     3: of primary importance; "basic truths" [syn: {basic}, {primary}]
Source: WordNet® 2.0