interminable, unfailingly, e'er, permanently, indefinite, infinitely, aye, endlessly, incessantly, lingering, continuing, world without end, always, ever, day in, day out, persistent, forevermore, long, protracted, unbroken, eternally, temporarily, continuously, lengthy, invariably, indelibly, unceasingly, everlasting, continual, continually, continuous, unceasing, unfailing, permanent, interminably, everlastingly, forever and a day, evermore, ceaselessly, unendingly, consistently, night and day, endless, long-drawn-out, constantly, perpetually
continuously (part of speech: adverb)
perpetuity (part of speech: noun)
indefinite duration (part of speech: noun)
- It goes on and on and on forever, and if you write it for a thousand years you are still as far from the end as when you began. - "A Rock in the Baltic", Robert Barr.
- " The war won't last forever," muttered Roger uneasily. - "His Family", Ernest Poole.
- But there will be a time when we shall forever be with the Lord. - "Heart Talks", Charles Wesley Naylor.