[awr-guh
n-pahyp] 
| a treelike or columnar cactus, Lemaireocereus marginatus, of Mexico, having a central, erect spine surrounded by spreading spines in clusters of five to eight, and funnel-shaped, brownish-purple flowers. |
| or·gan-pipe cactus (ôr'gən-pīp') n. A tall, treelike cactus (Lemaireocereus marginatus) native to central Mexico and the southwest United States. |
organ-pipe cactus
(species Pachycereus thurberi), plant belonging to the family Cactaceae, native to southern Arizona in the United States. Related species occur from Mexico to Venezuela and Peru and the West Indies. The name is also applied to a few other species of Pachycereus-like cacti that have several to many tall columns arising candelabra-like from the base or not far above it.
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