The most common and most likely answer to this crossword clue is the 5 letter word HEAPS
I've seen this crossword clue in Financial Times
H
E
A
P
S
More clues leading to the result HEAPS
Buddy explains!

The straight part
We know that "Very many" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case very many = heaps.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 HEAPS mean?
HEAPS noun- A crowd; a throng; a multitude or great number of people.
- A pile or mass; a collection of things laid in a body, or thrown together so as to form an elevation.
- A great number or large quantity of things.
- A data structure consisting of trees in which each node is greater than all its children.
- Memory that is dynamically allocated.
- A dilapidated place or vehicle.
- A lot, a large amount
- To pile in a heap.
- To form or round into a heap, as in measuring.
- To supply in great quantity.
- Very much, a lot