The most common and most likely answer to this crossword clue is the 5 letter word STRUT
I've seen this crossword clue in The Guardian
S
T
R
U
T
More clues leading to the result STRUT
- Walk ostentatiously to show support
- Peacock’s extremely short mating period
- Peacock in mating frenzy on the way
- Rod Stewart’s gutted with track
- Support belief son will rise to the top
- Prop displaying bulge, routine with stone put on
- Support for stone channel
- Maybe Rod Stewart’s tips to get groove
- Support walk in ostentatious style
- Swagger in support
Buddy explains!

The straight part
We know that "Support" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case support = strut.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 STRUT mean?
STRUT noun- Protuberance, air pressure
- To swell; protuberate; bulge or spread out.
- (originally said of fowl) To stand or walk stiffly, with the tail erect and spread out.
- To walk proudly or haughtily.
- To cause to swell; enlarge; give more importance to.
- To protrude; cause to bulge.
- A proud step or walk, with the head erect; affected dignity in walking.
- Swelling out; protuberant; bulging.
- A support rod.
- An instrument for adjusting the pleats of a ruff.
- To brace or support by a strut or struts; hold in place or strengthen by an upright, diagonal, or transverse support.