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look out for number one

idiom
Meaning

To act in one's own interests; to act in a manner advantageous primarily to oneself.


Origin

disputed origin

From look out for + number one (“oneself”). Attested since the 1830s at the latest.

Examples
SIMPLE

He always looks out for number one in every situation.

CONTEXTUAL

In this competitive industry, you must look out for number one if you want to succeed.

COMPLEX

She realized that her colleagues were only looking out for number one, so she stopped sharing her best ideas with them.

Anchors to
Related idioms8entries
  1. 01

    as best one can

    In the best possible way, given one's circumstances and abilities.

  2. 02

    as far as one knows

    To the best of one's knowledge, as far as someone knows or possible information to be gathered about the topic, subject, aspect, or situation.

  3. 03

    back to square one

    Located back at the start, as after a dead end or failure.

  4. 04

    beat as one

    To share the same feelings.

  5. 05

    become one flesh

    To join together in marriage; to develop a unifying bond as a result of marrying.

  6. 06

    bite off more than one can chew

    To try to do too much; to take on or attempt more than one is capable of doing.

  7. 07

    bite the big one

    To perform poorly; to fail.

  8. 08

    bite the hand that feeds one

    To cause harm to a benefactor (especially one that one is dependent on, thus with the idea that this behaviour is self-damaging).

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