The most common and most likely answer to this crossword clue is the 6 letter word SHAGGY
I've seen this crossword clue in The Guardian
S
H
A
G
G
Y
More clues leading to the result SHAGGY
- Unkempt, much like a cormorant?
- Tale in need of clipping?
- Boombastic singer‘s retiring to eat a horse
- With little confidence about a gang extremely unkempt
- Unkempt chap exhausted after long nap
- A couple of Germans in cast not well groomed
- Rough and coarse bird, outwardly gaudy
- Hairy, like a bird?
- Unkempt as a cormorant?
- Such a dog may be involved in many dubious accounts
Buddy explains!

The straight part
We know that "not well groomed" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case not well groomed = shaggy.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 SHAGGY mean?
SHAGGY adjective- With long, thick, and uncombed hair, fur or wool.
- With a surface like shaggy hair; rough nap.