The most common and most likely answer to this crossword clue is the 7 letter word IGNOBLE
I've seen this crossword clue in The Guardian
I
G
N
O
B
L
E
More clues leading to the result IGNOBLE
- Old coin found by soldier going over base
- Base of British Legion damage externally
- Returning priest restricting sound of bells? That's mean
- Some feel bong is backward and inferior
- Low, reverberating sound of bell that priest holds up
- . I belong for a change – that’s mean
- Mean goblin dancing close to pixie
- Vulgar new gin joint’s briefly set up
- Base doctor in “Globe”
- Soldier lifted head outside of Lebanese base
Buddy explains!

The straight part
We know that "base" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case base = ignoble.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 IGNOBLE mean?
IGNOBLE adjective- Not noble; plebeian; common.
- Not honorable; base.
- Not a true or "noble" falcon; said of certain hawks, such as the goshawk.