The most common and most likely answer to this crossword clue is the 4 letter word SPAZ
S
P
A
Z
Buddy explains!
The straight part
We know that "Lose control" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case lose control = spaz.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 SPAZ mean?
SPAZ noun- A stupid or incompetent person.
- A hyperactive person.
- A tantrum, a fit.
- To have a tantrum or fit.
- To malfunction, go on the fritz.