Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
vīvĭrādix, īcis, f. [vivus-radix], a set or cutting having a root, a layer, quickset; of the vine, Cato, R. R. 33, 4; Cic. Sen. 15, 52; Plin. 17, 22, 35, § 170; of the rose, Varr. R. R. 1, 35, 1.