The most common and most likely answer to this crossword clue is the 5 letter word POLEY
P
O
L
E
Y
Buddy explains!
The straight part
We know that "What Jock would call humble" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case what jock would call humble = poley.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 POLEY mean?
POLEY adjective- Without horns; polled.
- A whitish woolly plant (Teucrium polium) of the family Labiatae, found throughout the Mediterranean.