The most common and most likely answer to this crossword clue is the 7 letter word GNARLED
I've seen this crossword clue in The Times
G
N
A
R
L
E
D
More clues leading to the result GNARLED
Buddy explains!

The straight part
We know that "Rugged" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case rugged = gnarled.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 GNARLED mean?
GNARLED verb- To knot or twist something.
- To snarl or growl; to gnar.
- Knotty and misshapen.
- Made rough by age or hard work.
- To knot or twist something.
- To snarl or growl; to gnar.