The most common and most likely answer to this crossword clue is the 8 letter word AUDIENCE
I've seen this crossword clue in Financial Times
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More clues leading to the result AUDIENCE
- Interview poet outside one church
- Interview spectators
- Hearing bums on seats …
- Induce rehabilitation in hospital department for TV watchers?
- Interview expert about article in Die Welt probing multinational organisation
- Meeting house
- Car crash scene with groups of people watching
- They hear German car in French church
- Car space by church for important meeting
- Induce scuffling in hospital department hearing
Buddy explains!

The straight part
We know that "groups of people watching" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case groups of people watching = audience.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does AUDIENCE mean?
AUDIENCE noun- A group of people within hearing; specifically, a large gathering of people listening to or watching a performance, speech, etc.
- Hearing; the condition or state of hearing or listening.
- A widespread or nationwide viewing or listening public, as of a TV or radio network or program.
- A formal meeting with a state or religious dignitary.
- The readership of a book or other written publication.
- A following.
- An audiencia (judicial court of the Spanish empire), or the territory administered by it.