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Definitions

once upon a time

ADVERB
formerly
Synonyms
STRONGEST
already earlier heretofore once
STRONG
erstwhile
WEAK
a while back aforetime anciently at one time away back back back when before before now before this down memory lane eons ago erewhile in former times in the olden days in the past lately long ago of old of yore olden days radically some time ago time was used to be water under the bridge
Antonyms
WEAK
currently future presently subsequently
ADVERB
once
Synonyms
STRONGEST
already before earlier formerly late previously
STRONG
erstwhile
WEAK
a single time at one time away back back back when but once bygone heretofore in the old days in the olden days in times gone by in times past long ago old on one occasion once only one one time before one time previously only one time quondam sometime this time time was whilom
Antonyms
STRONGEST
currently future later presently

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

It was akin to all those hours I spent online once upon a time, dissecting clues down to their bones.

From Salon • Apr. 12, 2026

The author drops us into an Eden of wonder, where once upon a time we first cracked the codes of Dr. Seuss and “Goodnight Moon.”

From The Wall Street Journal • Mar. 1, 2026

Neil Findlay was a Labour MSP once upon a time.

From BBC • Sep. 3, 2025

According to the American Kennel Club, Great Danes were developed once upon a time by German nobles to hunt ferocious wild boars, and they later became beloved protectors of their home and loved ones.

From Los Angeles Times • Aug. 10, 2024

Her grandmother had tried to explain the magic to her, once upon a time.

From "The Girl Who Drank the Moon" by Kelly Barnhill