The most common and most likely answer to this crossword clue is the 7 letter word LUMPISH
I've seen this crossword clue in The Times
L
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More clues leading to the result LUMPISH
Buddy explains!

The straight part
We know that "Gross" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case gross = lumpish.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 LUMPISH mean?
LUMPISH adjective- Shaped like a lump, lumpy, ill-defined in shape.
- Like lumps, lumpy, composed of unshaped or mismatched pieces.
- Like a lump, cloddish, dull, slow-witted.
- Without energy, lethargic.
- Awkward, inelegant.