The most common and most likely answer to this crossword clue is the 10 letter word EGG-SHAPED
I've seen this crossword clue in Independent
E
G
G
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S
H
A
P
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More clues leading to the result EGG-SHAPED
Buddy explains!
The straight part
We know that "bigger at one end/ (3-6)" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case bigger at one end/ (3-6) = egg-shaped.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 EGG-SHAPED mean?
EGG-SHAPED adjective- Having the shape of an egg.