Definify.com

Webster 1913 Edition

Adj.

Armed with prickles, as a plant.

(Bot.)

Of, pertaining to, or resembling, the family of plants of which the acanthus is the type.

Adj.

Armed with prickles, as a plant.

acanthaceous ‎(comparative more acanthaceous, superlative most acanthaceous)

(botany): Of, pertaining to, or resembling, a member of the Acanthaceae family.[First attested in the mid 18th century.]^[2]
Armed with prickles, as a plant.

armed with prickles

pertaining to the acanthus family

↑ Urdang, Laurence, ed. The Random House College Dictionary. 1st. New York: Random House, Inc., 1984.
↑ Brown, Lesley, ed. The Shorter Oxford English Dictionary. 5th. Oxford: Oxford University Press, 2003.