Did you know?

Click any word in a definition or example to find the entry for that word

obsess - definition and synonyms

What are red words?

90% of the time, speakers of English use just 7,500 words in speech and writing. These words appear in red, and are graded with stars. One-star words are frequent, two-star words are more frequent, and three-star words are the most frequent.

Thesaurus diagram

The thesaurus of synonyms and related words is fully integrated into the dictionary. Click on the thesaurus category heading under the button in an entry to see the synonyms and related words for that meaning.

verb     obsess pronunciation in British English
Word Forms
present tense
present participleobsessing
past tenseobsessed
past participleobsessed
  1. 1
    [transitive] if someone or something obsesses you, they are so important to you that you are always thinking about them, in a way that seems extreme to other people

    The thought of seeing him again completely obsessed her.

    He was obsessed by a desire for revenge.

  2. 2
    [intransitive] to worry about something all the time
    obsess about/over:

    Joe’s always obsessing over his health.



a rainbow produced when water droplets in the air reflect light from the moon rather than the sun

BuzzWord Article

Open Dictionary

platform capitalism

a way of doing business that involves recruiting large numbers of people who work for themselves using the company's platform, as used by companies such as Uber, Deliveroo and the like

add a word


A must for anyone with an interest in the changing face of language. The Macmillan Dictionary blog explores English as it is spoken around the world today.

global English and language change from our blog
Macmillan learn live love play