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Definitions

day one

NOUN
beginning
Synonyms
STRONGEST
birth creation dawn inauguration inception introduction onset opening outset starting point top
STRONG
alpha basis blastoff commencement dawning genesis induction infancy initiation installation kickoff opener origin origination preface prelude presentation rise root rudiment source spring takeoff threshold
WEAK
point of departure square one
Antonyms
STRONGEST
conclusion death end ending finish
STRONG
close completion effect epilogue finale result termination
WEAK
consummation goal outcome
NOUN
incipience
Synonyms
STRONG
alpha basis birth blastoff commencement creation dawn dawning genesis inauguration inception incipiency induction infancy initiation installation introduction kickoff launch onset opener opening origin origination outset preface prelude presentation rise root rudiment source spring start takeoff threshold top
WEAK
leadoff point of departure square one starting point
Antonyms
STRONG
close completion conclusion death effect end ending epilogue finale finish result stop termination
NOUN
incipiency
Synonyms
STRONG
alpha basis birth blastoff commencement creation dawn dawning genesis inauguration inception incipience induction infancy initiation installation introduction kickoff launch onset opener opening origin origination outset preface prelude presentation rise root rudiment source spring start takeoff threshold top
WEAK
leadoff point of departure square one starting point
Antonyms
STRONG
close completion conclusion death effect end ending epilogue finale finish result stop termination
NOUN
leadoff
Synonyms
WEAK
alpha basis birth blastoff commencement creation dawn dawning genesis inauguration inception incipience incipiency induction infancy initiation installation introduction kickoff launch onset opener opening origin origination outset point of departure preface prelude presentation rise root rudiment source spring square one start starting point takeoff threshold top
NOUN
origin
Synonyms
STRONGEST
birth genesis
STRONG
alpha commencement creation dawn dawning embarkation emergence entrance entry forging foundation inauguration ingress initiation introduction launch nativity opener origination outbreak outset rise start
WEAK
blast off early stage git go square one starting point
Antonyms
STRONGEST
conclusion end finish
STRONG
close completion death ending exit stop
WEAK
consequence destiny effect finale goal outcome outgrowth result termination
NOUN
start
Synonyms
STRONGEST
beginning dawn kickoff opening outset
STRONG
birth commencement countdown dawning derivation embarkation foundation inauguration inception initiation introduction leaving onset origin source spring takeoff
WEAK
alpha arrival coming first step flying start jump-off running start setting-out square one start-off
Antonyms
STRONGEST
conclusion end ending finish
STRONG
close completion consequence death effect exit outgrowth result termination
WEAK
stop

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.

A huge component of “NCIS” that has remained consistent from day one is that it’s more than a case-of-the-week procedural.

From Los Angeles Times • Mar. 24, 2026

Iran's rulers have remained defiant despite their supreme leader, Ali Khamenei, being killed on day one.

From Barron's • Mar. 16, 2026

"It's like going back to day one," she says of their trauma.

From BBC • Mar. 7, 2026

We built everything ourselves from day one, which meant by the time we were running, we understood every part of the business at a granular level.

From MarketWatch • Mar. 5, 2026

From their home, on a clear day, one had a breathtaking view of Table Mountain with a thick cloud of fog hovering over Devil’s Peak.

From "Kaffir Boy: An Autobiography" by Mark Mathabane