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Synonyms

obsess

American  
[uhb-ses] / əbˈsɛs /

verb (used with object)

  1. to dominate or preoccupy the thoughts, feelings, or desires of (a person); beset, trouble, or haunt persistently or abnormally.

    Suspicion obsessed him.

    Synonyms:
    haunt, control, possess

verb (used without object)

  1. to think about something unceasingly or persistently; dwell obsessively upon something.

obsess British  
/ əbˈsɛs /

verb

  1. (tr; when passive, foll by with or by) to preoccupy completely; haunt

  2. (intr; usually foll by on or over) to worry neurotically or obsessively; brood

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

  • obsessingly adverb
  • obsessor noun

Etymology

Origin of obsess

1495–1505; < Latin obsessus, past participle of obsidēre to occupy, frequent, besiege, equivalent to ob- ob- + -sid ( ēre ) combining form of sedēre to sit 1

Explanation

If you obsess about something, you constantly think about it, like kids who obsess about their grades so much, they get upset before every test. Obsess comes from the Latin word obsessus, which means to besiege, the way obsessive thoughts can besiege, or attack, your mind. You can obsess about something, like the tiny spot on your shoes that no one can even see, or be obsessed, or haunted or preoccupied by something. For example, the memory of a big, delicious dinner could obsess a hungry man.

Keep Reading on Vocabulary.com

Vocabulary lists containing obsess

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’s the least visible part of my body, yet I’ve had good reason lately to obsess about my gluteus maximus, my derrière, my whole imperfect situation back there.

From Slate • Feb. 22, 2026

Some obsess over the chaotic storyline in which a young boy, Kevin McCallister—played by Macaulay Culkin—is abandoned home alone by his family as they jet off on a trip to Paris for the holiday season.

From MarketWatch • Dec. 29, 2025

But they obsess, with good reason, over one stat above all others: turnovers.

From The Wall Street Journal • Dec. 21, 2025

"If you obsess so much on youth that will bite you on the bum, unfortunately."

From BBC • Oct. 31, 2025

I always obsess on what others think of me, even stupid mean girls like Maddy and Stephanie.

From "A Place at the Table" by Saadia Faruqi and Laura Shovan