Word Study
lifelong
CIDE DICTIONARY
lifelong, a. [Life + long. Cf. Livelong.].
Lasting or continuing through life. Tennyson. [1913 Webster]
ROGET THESAURUS
lifelong
Diuturnity
N diuturnity, a long time, a length of time, an age, a century, an eternity, slowness, perpetuity, blue moon, coon's age, dog's age, durableness, durability, persistence, endlessness, lastingness, continuance, standing, permanence, survival, survivance, longevity, distance of time, protraction of time, prolongation of time, extension of time, delay, durable, lasting, of long duration, of long-standing, permanent, endless, chronic, long-standing, intransient, intransitive, intransmutable, persistent, lifelong, livelong, longeval, long-lived, macrobiotic, diuturnal, evergreen, perennial, sempervirent, sempervirid, unrelenting, unintermitting, unremitting, perpetual, lingering, protracted, prolonged, spun out, long-pending, long-winded, slow, long, for a long time, for an age, for ages, for ever so long, for many a long day, long ago, longo intervallo, all the day long, all the year round, the livelong day, as the day is long, morning noon and night, hour after hour, day after day, for good, permanently.For further exploring for "lifelong" in Webster Dictionary Online