The most common and most likely answer to this crossword clue is the 8 plus 6 letter word ELECTRIC GUITAR
I've seen this crossword clue in The Daily Telegraph
E
L
E
C
T
R
I
C
G
U
I
T
A
R
More clues leading to the result ELECTRIC GUITAR
- Plucky types may use one, subject to current availability
- , 21 Feature of rock or glacier with tier cut out
- Axe trite “cigar” clue, poor
- Tragic ruin, almost destroyed by pick axe
- Urge late critic developed to get instrument
- Possibly alter circuit, e.g. for this instrument
- Ingredient for making rock — mix it with treacle and put in three parts of rice and two of gum
- Let critic argue for arrangement that needs amplifying
Buddy explains!
The straight part
We know that "instrument" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case instrument = electric guitar.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.