What Does IDU Mean in a Text?

IDU means "I Don't Understand." The abbreviation IDU is used to indicate that the sender does not understand a statement or situation; i.e., they don't know the meaning of what has been said or cannot grasp why something has happened.

Image for IDU

When I write IDU, I mean this:

meaning of IDU

IDU indicates a lack of comprehension.

Summary of Key Points

"I Don't Understand" is the most common definition for IDU on Snapchat, WhatsApp, Facebook, Twitter, Instagram, and TikTok.
Definition:I Don't Understand
Guessability:guessability level 4
4: Difficult to guess
Typical Users:typical user

Adults and Teenagers

Examples of IDU in Sentences

Here are examples of IDU being used in conversations:
  • Jack: Light takes one hour to travel from one side of a giant star to the other.
  • Lewis: IDU. Does that mean stars spend half their time in darkness?
  • Sarah: I'm leaving the company on Friday.
  • Ryan: What? IDU. Why?

An Academic Look at IDU

IDU is an initialism abbreviation. Technically, this means it is pronounced using its individual letters (i.e., Eye Dee Yu). However, it is not often spoken using its letters. The abbreviation IDU is for efficiency in writing and not efficiency in speech.

What Did We Say before Texting and Social Media?

Before the digital era, we might have just said "I Don't Understand" or something like "Pardon?" instead of using IDU.

Example of IDU Used in a Text

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