The most common and most likely answer to this crossword clue is the 7 letter word TOSSPOT
I've seen this crossword clue in Independent
T
O
S
S
P
O
T
More clues leading to the result TOSSPOT
- Possible little drop of spirits for Spooner to get drunk
- Kitty supports shy drunkard
- Drunken sot with pint, so drunk
- See beyond endless baloney in stupid individual
- Old drunk drunks facing off around back of Co-op
- Drunkard covers another’s back
- Contemptible type of introduction for Trump: “outstanding mark”
- Throw crockery at old drunk
- Drunkard of yore you’ll get to see without glass, ultimately
- Stupid sap to s-see?
Buddy explains!

The straight part
We know that "Stupid sap" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case stupid sap = tosspot.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 TOSSPOT mean?
TOSSPOT noun- A drunkard, one who drinks alcohol frequently.
- A fool, prat; an idiot.