Here are some synonyms for "detect":
* Discover
* Notice
* Perceive
* Recognize
* Identify
* Find
* Uncover
* Spot
* Observe
Examples:
* The doctor detected an early sign of cancer in the patient's blood test.
* The security system detected an intruder in the building.
* The police detected a suspicious odor coming from the house.
* Scientists have detected evidence of water on Mars.
Usage:
* Detect is often used in contexts related to sensing, observing, or identifying something that is not immediately obvious or visible.
* It can be used with a variety of objects or phenomena, including physical objects, changes in the environment, diseases, and emotions.
* It can be used in both formal and informal writing.