The Collaborative International Dictionary of English v.0.48:

Sequoia \Se*quoi"a\, n. [NL. So called by Dr. Endlicher in honor
   of Sequoyah, who invented the Cherokee alphabet.] (Bot.)
   A genus of coniferous trees, consisting of two species,
   Sequoia Washingtoniana, syn. Sequoia gigantea, the "big
   tree" of California, and Sequoia sempervirens, the redwood,
   both of which attain an immense height.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Sequoiene \Se*quoi"ene\, n. (Chem.)
   A hydrocarbon (C13H10) obtained in white fluorescent
   crystals, in the distillation products of the needles of the
   California "big tree" (Sequoia gigantea).
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Wellingtonia \Wel`ling*to"ni*a\, n. [NL. So named after the Duke
   of Wellington.] (Bot.)
   A name given to the "big trees" (Sequoia gigantea) of
   California, and still used in England. See Sequoia.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Sequoia gigantea
    n 1: extremely lofty evergreen of southern end of western
         foothills of Sierra Nevada in California; largest living
         organism [syn: giant sequoia, big tree, Sierra
         redwood, Sequoiadendron giganteum, Sequoia gigantea,
         Sequoia Wellingtonia]