The most common and most likely answer to this crossword clue is the 7 letter word TREKKER
I've seen this crossword clue in The Guardian
T
R
E
K
K
E
R
More clues leading to the result TREKKER
Buddy explains!
The straight part
We know that "Pioneering South African/TV series fan" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case pioneering south african/tv series fan = trekker.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 TREKKER mean?
TREKKER noun- One who treks; thus, a hiker.
- (World War II) A person who spent the night in a rural area, rather than his home, during bombing raids.