The most common and most likely answer to this crossword clue is the 9 letter word AMORPHOUS
I've seen this crossword clue in The Times
A
M
O
R
P
H
O
U
S
More clues leading to the result AMORPHOUS
Buddy explains!
The straight part
We know that "Shapeless" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case shapeless = amorphous.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 AMORPHOUS mean?
AMORPHOUS adjective- Lacking a definite form or clear shape.
- (by extension) Being without definite character or nature.
- (by extension) Lacking organization or unity.
- In the non-crystalline solid state of a typically crystalline solid.
- (of a set) Infinite and not the disjoint union of two infinite subsets.