Source : Webster's Revised Unabridged Dictionary (1913)

Sego \Se"go\, n. (Bot.)
   A liliaceous plant ({Calochortus Nuttallii}) of Western North
   America, and its edible bulb; -- so called by the Ute Indians
   and the Mormons.

Source : WordNet®

Calochortus nuttallii
     n : perennial plant having umbellike clusters of one to four
         showy white bell-shaped flowers atop erect unbranched
         stems; edible bulbs useful in times of scarcity; eastern
         Montana and western North Dakota south to northern
         Arizona and northwestern New Mexico [syn: {sego lily}]