The most common and most likely answer to this crossword clue is the 6 letter word ROARED
I've seen this crossword clue in Financial Times
R
O
A
R
E
D
More clues leading to the result ROARED
Buddy explains!
The straight part
We know that "howled" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case howled = roared.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 ROARED mean?
ROARED verb- To make a loud, deep cry, especially from pain, anger, or other strong emotion.
- To laugh in a particularly loud manner.
- Of animals (especially the lion), to make a loud deep noise.
- Generally, of inanimate objects etc., to make a loud resounding noise.
- To proceed vigorously.
- To cry aloud; to proclaim loudly.
- To be boisterous; to be disorderly.
- To make a loud noise in breathing, as horses do when they have a certain disease.
- (North Midlands) to cry