Available Definitions:
1) a. - ing or continuing through the year; as, perennial fountains.
2) a. - Continuing without cessation or intermission; perpetual; unceasing; never failing.
3) a. - Continuing more than two years; as, a perennial steam, or root, or plant.
4) n. - A perennial plant; a plant which lives or continues more than two years, whether it retains its leaves in winter or not.