The Collaborative International Dictionary
Monocarpic \Mon`o*car"pic\, Monocarpous \Mon`o*car"pous\, a. [Mono- + Gr. ? fruit: cf. F. monocarpe.] (Bot.) Bearing fruit but once, and dying after fructification, as beans, maize, mustard, etc.
Note: Annual and biennual herbs are monocarpic, so also some plants of longer duration, as the century plant.
Wiktionary
a. (context botany English) (''of a plant'') That flowers and bears fruit only once before dying
WordNet
adj. dying after bearing fruit only once
Wikipedia
Monocarpic plants are those that flower, set seeds and then die. Other terms with the same meaning are hapaxanth and semelparous. The term was first used by Alphonse de Candolle.
The antonym is polycarpic, a plant that flowers and sets seeds many times during its lifetime; the antonym of semelparous is iteroparous. Plants which flower en masse (gregariously) before dying are known as plietesials.
The plant can live a number of years before it will flower. Flowering does not by itself result in the death of the plants but the production of fruits and seeds causes changes within the plants which lead to death. These changes are induced by chemicals that act as hormones, redirecting the resources of the plants from the roots and leaves to the production of fruits and or seeds.
The century plant in the genus Agave, some terrestrial bromeliads of the genus Puya, Tillandsia utriculata, some yuccas, and many bamboos can take 8 to 20 years or in the case of bamboos even over 100 years to bloom and then die. Hawaiian silverswords and their relatives in the genus Wilkesia may take 10–50 years before flowering.
Monocot plant families which contain monocarpic species include Agavaceae, Araceae, Arecaceae, Bromeliaceae, Musaceae and Poaceae. Dicot plant families which include monocarpic species include Acanthaceae, Apocynaceae, Asteraceae, and Fabaceae. Few dicot shrubs with multiple branching and secondary growth species have been described. Those that have include Strobilanthes species, Cerberiopsis candelabrum, Tachigali versicolor and other Tachigali species.
Often monocarpic plants can be kept alive after flowering if the flowers are removed as soon as they have finished blooming, before seed formation begins, or if the flower buds are removed before they begin blooming.