noun \ī-ˈdē-ə, -ˈdēə also ˈī-(ˌ)dē-ə or ˈī-dē\

Definition of idea

  1. 1a :  a transcendent entity that is a real pattern of which existing things are imperfect representationsb :  a standard of perfection :  idealc :  a plan for action :  design

  2. 2 archaic :  a visible representation of a conception :  a replica of a pattern

  3. 3a obsolete :  an image recalled by memoryb :  an indefinite or unformed conceptionc :  an entity (as a thought, concept, sensation, or image) actually or potentially present to consciousness

  4. 4 :  a formulated thought or opinion

  5. 5 :  whatever is known or supposed about something a child's idea of time

  6. 6 :  the central meaning or chief end of a particular action or situation

  7. 7 Christian Science :  an image in Mind


play \ī-ˈdē-ə-ləs, -ˈdēə- also ˈī-(ˌ)dē-ə- or ˈī-dē-\ adjective

Examples of idea in a sentence

  1. My idea is to study law.

  2. Starting her own business seemed like a good idea at the time, but it turned out badly.

  3. Whose idea was it to leave so early?

  4. My idea was that if we left early we could beat the crowd.

  5. Buying the car was a bad idea.

  6. I have some ideas for redecorating the room.

  7. He has an idea for a movie.

  8. I'm not sure what to do next. Do you have any ideas?

  9. She's always full of new ideas.

  10. It's a good idea to talk to people who have actually been there.

Origin and Etymology of idea

Middle English, from Latin, from Greek, from idein to see — more at wit

First Known Use: 14th century

Synonym Discussion of idea

idea, concept, conception, thought, notion, impression mean what exists in the mind as a representation (as of something comprehended) or as a formulation (as of a plan). idea may apply to a mental image or formulation of something seen or known or imagined, to a pure abstraction, or to something assumed or vaguely sensed innovative ideas my idea of paradise. concept may apply to the idea formed by consideration of instances of a species or genus or, more broadly, to any idea of what a thing ought to be a society with no concept of private property. conception is often interchangeable with concept ; it may stress the process of imagining or formulating rather than the result our changing conception of what constitutes art. thought is likely to suggest the result of reflecting, reasoning, or meditating rather than of imagining commit your thoughts to paper. notion suggests an idea not much resolved by analysis or reflection and may suggest the capricious or accidental you have the oddest notions. impression applies to an idea or notion resulting immediately from some stimulation of the senses the first impression is of soaring height.

IDEA Defined for English Language Learners


noun \ī-ˈdē-ə, -ˈdēə also ˈī-(ˌ)dē-ə or ˈī-dē\

Definition of idea for English Language Learners

  • : a thought, plan, or suggestion about what to do

  • : an opinion or belief

  • : something that you imagine or picture in your mind

IDEA Defined for Kids


noun \ī-ˈdē-ə\

Definition of idea for Students

  1. 1 :  a thought or plan about what to do Surprising her was a bad idea.

  2. 2 :  something imagined or pictured in the mind I had an idea of what the town was like.

  3. 3 :  an understanding of something I have no idea what you mean.

  4. 4 :  a central meaning or purpose The idea of the game is to keep from getting caught.

  5. 5 :  an opinion or belief What gave you that idea?

Medical Dictionary

noun \ī-ˈdē-ə, ˈīd-(ˌ)ē-ə\

Medical Definition of idea

  1. 1:  an entity (as a thought, concept, sensation, or image) actually or potentially present to consciousness

  2. 2:  a formulated thought or opinion

Seen and Heard

What made you want to look up idea? Please tell us where you read or heard it (including the quote, if possible).


a dividing ridge between drainage areas

Get Word of the Day daily email!


Take a 3-minute break and test your skills!

  • shamrock
  • What is the best definition of green-eyed monster?
Name That Thing

Test your visual vocabulary with our 10-question challenge!


Test Your Knowledge - and learn some interesting things along the way.