“What is the matter?” usually means “What’s wrong?” or “What’s the problem?” in everyday English.

Everyday meaning

When someone asks “What is the matter?” they are asking if something is bothering you, hurting you, or not working as it should.

Typical uses:

  • If you look sad or upset: “You’re very quiet today—what is the matter?”
  • If something isn’t working: “The computer keeps freezing; what is the matter with it?”

In these cases:

  • “the matter” = the problem, difficulty, or reason for worry.

Where “matter” comes from in this phrase

The word “matter” has several meanings, but in “what is the matter?” it means “the situation, subject, or problem being dealt with.”

Key senses:

  • A situation or subject that is being considered: a “personal matter,” “a serious matter.”
  • The reason for pain or worry: “What’s the matter? Why are you so upset?”

So the phrase is literally asking: “What is the problem/situation (with you/this thing)?”

Other meanings of “matter” (for context)

Outside this expression, “matter” can also mean:

  • Physical substance that has mass and takes up space (in science and physics).
  • A type of substance or printed material (“vegetable matter,” “printed matter”).

But in common speech, if someone says “What is the matter?”, they are almost always asking about a problem or what’s wrong , not about physical substance.

Mini example “forum-style” snippet

“My friend keeps asking me ‘What is the matter?’ whenever I’m quiet. It just means they’re checking if something is wrong or if I want to talk about a problem.”

TL;DR: In normal conversation, “what is the matter?” = “what’s wrong?” / “what’s the problem?”