The most common and most likely answer to this crossword clue is the 5 letter word SONDE
S
O
N
D
E
Buddy explains!
The straight part
We know that "Probe" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case probe = sonde.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 SONDE mean?
SONDE noun- Probe; sound.
- (physical sciences) Any of various devices for testing physical conditions, often for remote or underwater locations.