The most common and most likely answer to this crossword clue is the 6 letter word INRUSH
I
N
R
U
S
H
More clues leading to the result INRUSH
- Sudden move to the centre in close-pressed crowd losing its head
- Sudden flood of arrivals ruins new hospital
- Quick entry for fashionable plant
- Crowd invasion when area lost by Liverpool striker
- Quick move to forward at Liverpool, not Arsenal first
- Sudden arrival of cleaner making Bishop popular
- Out of the area, old Liverpool striker makes sudden arrival
- Sudden influx of popular crowd having missed the start
- Sudden surge of current essentially ruining riverside plant
- Sudden arrival sadly ruins start of holiday
Buddy explains!

The straight part
We know that "Crowd invasion" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case crowd invasion = inrush.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 INRUSH mean?
INRUSH noun- A crowding or flooding in.
- The initial flow of electricity into a component when it is switched on.
- To rush in.