The most common and most likely answer to this crossword clue is the 4 letter word TOBY
I've seen this crossword clue in Financial Times
T
O
B
Y
More clues leading to the result TOBY
- Man and dog associated with jug
- Kids into robbery perhaps, lives looked into by the Met?
- Belch, perhaps, in play touring Belgium
- Young British journalist attached to Times
- Model hugging British mug
- Foremost of brews served in miniature beer mug
- Name on jug for sale, less posh
- Mug bowled during play
- Mug bishop during play
- Earthenware pot bishop brought into model prison?
Buddy explains!

The straight part
We know that "Belch, perhaps" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case belch, perhaps = toby.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 TOBY mean?
TOBY noun- A drinking mug, in the shape of a human head with a hat atop.
- The valve that mediates the connection between a mains water-supply and a premises's own plumbing.
- The road or highway.
- A kind of inferior cigar of a long slender shape, tapered at one end.
- The Moorish idol, Zanclus cornutus
- Any of several species of pufferfish in the genus Canthigaster