The most common and most likely answer to this crossword clue is the 8 letter word SMIDGEON
I've seen this crossword clue in The Guardian
S
M
I
D
G
E
O
N
More clues leading to the result SMIDGEON
- A little boy catches fly
- A little boy swallowing an insect
- A little insect eaten by son
- Initially see little fellow working for a very small amount
- Kid about a biter bit
- Bit by dog, mine unfortunately, after seconds
- Boy catching gnat gets bit
- Returns two-thirds of Chinese appetizer, having gone off a bit
- Little boy catches bug
- Trace amount left around in goldmines
Buddy explains!

The straight part
We know that "bit/bit" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case bit/bit = smidgeon.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 SMIDGEON mean?
SMIDGEON noun- A very small quantity or amount.