coincidental

adjective

co·​in·​ci·​den·​tal (ˌ)kō-ˌin(t)-sə-ˈden-tᵊl 

1

: resulting from a coincidence

a coincidental resemblance

2

: occurring or existing at the same time

coincidental deaths

Synonyms of coincidental

• coincident
• concurrent
• synchronous
• synchronic

Examples of coincidental in a Sentence

The fact that he and his boss went to the same college was purely coincidental.

the nearly coincidental deaths of Princess Diana and Mother Teresa

Recent Examples on the Web

The specificity of that result — improvement only in wet conditions — is exactly what an adaptive hypothesis predicts and what a coincidental explanation cannot easily account for. —Scott Travers, Forbes.com, 22 May 2026

The resemblance to Venice isn’t coincidental. —Erica Firpo, Travel + Leisure, 21 May 2026

Rosenberg crafts these two characters with realistic resonance, though his film veers into sentimentality and some plot points are too coincidental to be entirely believable. —Murtada Elfadl, Variety, 19 May 2026

The timing is not coincidental. —Lin Cherry, Fortune, 17 May 2026

Word History

Etymology

coincident + -al entry 1

First Known Use

circa 1800, in the meaning defined at sense 1

Rhymes for coincidental

• accidental
• compartmental
• continental
• detrimental
• elemental
• fundamental
• governmental
• incidental
• incremental
• instrumental
• interdental
• monumental

Kids Definition

coincidental

adjective

co·​in·​ci·​den·​tal (ˌ)kō-ˌin(t)-sə-ˈdent-ᵊl 

1

: resulting from a coincidence

a coincidental resemblance

2

: occurring or existing at the same time

coincidentally

-ˈdent-lē, 

-ᵊl-ē

adverb