Perpetual, a.
Etymology: [OE. perpetuel, F. perpétuel, fr. L. perpetualis, fr. perpetuus continuing throughout, continuous, fr. perpes, -etis, lasting throughout.]
Neverceasing; continuing forever or for an unlimited time; unfailing; everlasting; continuous. Unto the kingdom of perpetual night. Shak. Perpetual feast of nectared sweets. Milton. Circle of perpetual apparition, or occultation. See under Circle. -- Perpetual calendar, a calendar so devised that it may be adjusted for any month or year. -- Perpetual curacy (Ch. of Eng.), a curacy in which all the tithes are appropriated, and no vicarage is endowed. Blackstone. -- Perpetual motion. See under Motion. -- Perpetual screw. See Endless screw, under Screw.
Syn. -- Continual; unceasing; endless; everlasting; incessant; constant; eternal. See Constant.
Shades of meaning
Fernald has no entry of its own for perpetual; he lists it under continual, eternal, permanent.
He lists it without comment; the entries above explain its neighbors.