significant other

American  

noun

1. Sociology. a person, as a parent or peer, who has great influence on one's behavior and self-esteem.

2. a spouse or cohabiting lover. SO, S.O.

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significant other British  

noun

1. informal a spouse or lover

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Compare meaning

How does significant-other compare to similar and commonly confused words? Explore the most common comparisons:

• significant other vs. girlfriend

Example Sentences

Participants also answered questions about how satisfied they felt with their spouse or significant other, how much conflict they experienced in communication, and how confident they were that their relationship would last.

From Science Daily • Feb. 14, 2026

“There’s no sense of urgency to make sure their spouse or significant other is well taken care of.”

From MarketWatch • Jan. 21, 2026

The FBI thought the lead was promising enough to launch an undercover investigation, people familiar with it said, with a covert agent befriending the woman’s significant other to elicit new clues.

From The Wall Street Journal • Dec. 14, 2025

Under no circumstances, that is, do we approve of Surge content being consumed in a bathroom by someone who has already told their significant other that they’ll “be down in a minute.”

From Slate • Jul. 26, 2025

What they found was there was a decided increase in the sense of urgency when the text came from a significant other, as opposed to a friend or more distant acquaintance.

From "A Deadly Wandering: A Mystery, a Landmark Investigation, and the Astonishing Science of Attention in the Digital Age" by Matt Richtel