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Definitions

firstly

[furst-lee] / ˈfɜrst li /
ADVERB
basically
Synonyms
STRONGEST
essentially mostly
WEAK
at heart at the bottom in essence in substance inherently intrinsically primarily radically
Antonyms
WEAK
additionally extra inessentially
ADVERB
first off
Synonyms
WEAK
first of all first thing foremost immediately in the first place primo up front
ADVERB
radically
Synonyms
STRONGEST
essentially
WEAK
basically fundamentally primarily primitively

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.

Firstly, he said, there’s the “fog of war,” where like during World War II, stocks bottom early into a conflict.

From MarketWatch • Apr. 16, 2026

Firstly, while you are standing there pouting, our opponents are racing to their basket with a five-on-four advantage.

From Los Angeles Times • Apr. 4, 2026

Firstly, it’s not new—a technical draft of research on the algorithm appeared online in April 2025.

From Barron's • Mar. 26, 2026

Firstly, he will have put his club in pole position to qualify for the Champions League, which few thought was realistic when he stepped into Amorim's shoes.

From BBC • Mar. 4, 2026

Firstly, I had no idea how to tie a bow tie.

From "Tradition" by Brendan Kiely