The most common and most likely answer to this crossword clue is the 6 letter word ROTUND
I've seen this crossword clue in The Guardian
R
O
T
U
N
D
More clues leading to the result ROTUND
- Heavy drinks bottles heading for tavern
- What's Falstaff like? A large cask in a bar
- Stick round beer cask, spherical
- Big barrel grabbed by stick
- Heavy barrel secured by cane
- Stout from barrel in bar
- Plump finally for Oxford after vacation drinking much ale
- Podgy about right, ultimately?
- Plump angler’s aid to catch majority of fish
- Full barrel in bar
Buddy explains!

The straight part
We know that "Heavy/Heavy" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case heavy/heavy = rotund.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 ROTUND mean?
ROTUND adjective- Having a round or spherical shape; circular; orbicular.
- Having a round body shape; portly or plump; podgy.
- (of a sound) Full and rich; orotund; sonorous; full-toned.