To detect means to find or see something that is not easy to find. People use it when they want to say they noticed or discovered something.
I detect a strange smell in the room.
The dog can detect hidden food.
Detect can also mean to find something with a machine or sensor, like smoke or movement. Machines or devices help to find things that people cannot see.
The alarm can detect smoke quickly.
Sensors detect movement in the room.
In medicine or science, to detect means to find signs of a disease or condition using tests or examinations. It helps doctors know if someone is sick.
Tests can detect illness early.
Doctors detect a fever in the patient.
Detect means to find something hidden that is bad or against rules. It is often used when police or computers find crimes or problems.
Police detect fraud in the company.
The software can detect hackers quickly.
To detect can also mean to see or feel that something is happening, even if it is not shown clearly. It means understanding a small sign or feeling.
He detected a change in her mood.
I detect that you are tired today.
Sometimes detect means to find proof or signs that show something is true. Scientists often detect facts by looking carefully and using experiments.
Scientists detect signals from space.
Experiments detect signs of life.
