The most common and most likely answer to this crossword clue is the 8 letter word SPORADIC
I've seen this crossword clue in The Times
S
P
O
R
A
D
I
C
More clues leading to the result SPORADIC
- Backed some police operations involving men with guns now and then
- Picadors, when thrown, scattered
- Crop said to be failing, having big gaps
- Isolated police officers brought back to catch wicked one
- Detectives are ditching English operations, backtracking on an irregular basis
- Scattered crop said to be spoilt
- Random policemen turning up to house heading to room with a detective
- Cook prosaic about top of dish being irregular
- Erratic mounted police contain riotous raid
- Picadors are involved here and there
Buddy explains!

The straight part
We know that "having big gaps" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case having big gaps = sporadic.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 SPORADIC mean?
SPORADIC adjective- (of diseases) occurring in isolated instances; not epidemic.
- Rare and scattered in occurrence.
- Exhibiting random behavior; patternless.