The most common and most likely answer to this crossword clue is the 4 letter word SKEG
S
K
E
G
Buddy explains!
The straight part
We know that "The back actually" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case the back actually = skeg.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 SKEG mean?
SKEG noun- A fin-like structure to the rear of the keel of a vessel that supports the rudder and protects a propeller.
- A similar construction on a boat that acts as a keel.
- A fin that serves to stabilize a surfboard.
- A surfer; a person who leads a surfing lifestyle.
- A sort of wild plum (Prunus spinosa or Prunus domestica subsp. insititia (syn. Prunus institia)).
- A kind of oat.