perennial

American Heritage® Dictionary of the English Language, Fourth Edition

1. adj. Lasting or active through the year or through many years.
2. adj. Lasting an indefinitely long time; enduring: perennial happiness.
3. adj. Appearing again and again; recurrent. See Synonyms at continual.
4. adj. Botany Living three or more years.
5. n. Botany A perennial plant.
6. n. Something that recurs or seems to recur on a yearly or continual basis: "that hardy perennial, the budget deficit” ( David S. Broder).

Century Dictionary and Cyclopedia

1. Lasting or continuing without cessation through the year, or through many years: as, a perennial spring or fountain.
2. Continuing without stop or intermission; perpetual; unceasing; never-failing; everlasting.
3. In zoology, growing continually: noting teeth which have the pulp-cavity open, and grow indefinitely from persistent pulps: as, the perennial incisors of a rodent.
4. In botany, continuing more than two years: as, a perennial stem or root.
5. In entomology, forming colonies which are continued from year to year, as the ants, bees, and termites; also, living more than one year, as an insect. Synonyms Unfailing, enduring, permanent, constant, abiding, lasting, undying, imperishable, deathless, immortal.
6. n. In botany, a plant which lives and blossoms or fructifies year after year. Such plants may or may not have perennial roots. In trees and shrubs and herbs with growth from year to year from a strong taproot the root is naturally perennial; but in most perennials with only fibrous roots the roots are produced anew from time to time or from year to year. The division of plants into annuals, biennials, and perennials, according to the duration of their roots, is liable to vary under the influence of different circumstances. An annual plant in a northern climate may become a biennial or even a perennial in a warm climate, while, on the other hand, the perennials of warm climates often become annuals when transplanted to northern climates.

Wiktionary

1. adj. Lasting or remaining active throughout the year, or all the time.
2. adj. botany, of a plant Having a life cycle of more than two years. Compare annual, biennial.
3. adj. figuratively Continuing without cessation or intermission; perpetual; permanent; unceasing; never failing.
4. adj. figuratively Enduring; lasting; timeless.
5. adj. figuratively Recurrent; appearing or recurring again and again.
6. n. A perennial plant; a plant that is active throughout the year or survives for more than two growing seasons. Compare annual, biennial.

GNU Webster's 1913

1. adj. ing or continuing through the year.
2. adj. Continuing without cessation or intermission; perpetual; unceasing; never failing.
3. adj. (Bot.) Continuing more than two years.
4. n. (Bot.) A perennial plant; a plant which lives or continues more than two years, whether it retains its leaves in winter or not.

WordNet 3.0

1. adj. lasting an indefinitely long time; suggesting self-renewal
2. n. (botany) a plant lasting for three seasons or more
3. adj. recurring again and again
4. adj. lasting three seasons or more