Tra từ detect - Từ điển Oxford Advanced Learner 8th

de·tect AW [detect detects detected detecting] BrE [dɪˈtekt] NAmE [dɪˈtekt] verb ~ sth
to discover or notice sth, especially sth that is not easy to see, hear, etc
•The tests are designed to detect the disease early.
•an instrument that can detect small amounts of radiation
•Do I detect a note of criticism?
Derived Word: ↑detectable
Verb forms:

Word Origin:
late Middle English: from Latin detect- ‘uncovered’, from the verb detegere, from de- (expressing reversal) + tegere ‘to cover’. The original senses were ‘uncover, expose’ and ‘give someone away’, later ‘expose the real or hidden nature of’; hence the current senses (partly influenced by ↑detective).

Synonyms:
notice
note • detect • observe • witness
These words all mean to see sth, especially when you pay careful attention to it.
notice • to see, hear or become aware of sb/sth; to pay attention to sb/sth: ▪ The first thing I noticed about the room was the smell.
note • (rather formal) to notice or pay careful attention to sth: ▪ Please note (that) the office will be closed on Monday.
This word is very common in business English: ▪ Note that the prices are inclusive of VAT.
detect • to discover or notice sth, especially sth that is not easy to see, hear, etc: ▪ The tests are designed to detect the disease early.
observe • (formal) to see or notice sb/sth: ▪ Have you observed any changes lately? ◇ ▪ The police observed a man enter the bank.
witness • (rather formal) to see sth happen: ▪ Police have appealed for anyone who witnessed the incident to contact them.
to notice/note/detect/observe that/how/what/where/who…
to notice/observe/witness sth happen/sb do sth

Example Bank:
•Some cancers can now be cured if they are detected early.
•Some substances can be detected fairly easily.
•The test failed to detect any illegal substances.
•a machine that is sensitive enough to detect tiny amounts of explosives
•Do I detect a note of criticism in your voice?
•These creatures are so small they would be impossible to detect with the human eye.
•This is an instrument that can detect very small amounts of radiation.