What does "surveillance" mean?

1. (security monitoring) the act of watching a person or place carefully, often using cameras or technology, to stop crime. 2. (medical monitoring) the process of tracking how a disease spreads to keep people safe.

How do you use "surveillance"?

Often used as an uncountable noun or as a modifier in phrases like 'surveillance equipment' or 'surveillance footage'. Commonly appears in the phrase 'public health surveillance'.

surveillance

US //sɝˈveɪɫəns// UK //səvˈeɪləns// sur·veil·lance

1 security monitoring (n.)
C1 Advanced Formal Law

the act of watching a person or place carefully, often using cameras or technology, to stop crime.

the systematic observation of places or persons by visual, electronic, or other technical means for security or investigative purposes.

Example

The bank installed new surveillance cameras to watch the entrance 24 hours a day.

Example

The intelligence agency maintained constant electronic surveillance on the suspect's communications to identify potential accomplices.

Usage

Often used as an uncountable noun or as a modifier in phrases like 'surveillance equipment' or 'surveillance footage'.

Teacher's tip

Learners often misspell this word; remind them of the double 'l' and the 'ei' sequence.
2 medical monitoring (n.)
C1 Advanced Technical Medicine

the process of tracking how a disease spreads to keep people safe.

the continuous, systematic collection and analysis of health data for the planning and evaluation of public health practice.

Example

Health officials used disease surveillance to find out where the flu was spreading fastest.

Example

Epidemiological surveillance is critical for detecting early signs of an outbreak before it reaches a pandemic scale.

Usage

Commonly appears in the phrase 'public health surveillance'.

Teacher's tip

In this context, the word is almost always uncountable.
- tracking
- monitoring

Origin

Unadapted borrowing from French surveillance (“a watching over, overseeing, supervision”), from surveiller (“to watch, oversee”), from sur- (“over”) + veiller (“to watch”), from Middle French, from Old French veillier (“to stay awake”), from Latin vigilāre (“to be watchful”). More at vigilant.