The most common and most likely answer to this crossword clue is the 7 letter word YAWNING
I've seen this crossword clue in Financial Times
Y
A
W
N
I
N
G
More clues leading to the result YAWNING
- After end of day canvas shelter is wide open
- Gaping opening in yacht’s canopy
- Canopy, after year, showing sign of fatigue?
- Back of grey canopy is wide open
- The top of your canopy is wide open
- Drowsy and moving unsteadily, about close to exhaustion
- Shelter after day’s end, showing weariness?
- Shelter at back of yard, showing sign of tiredness?
- Yes, canvas shelter is wide open
- Huge yard with canopy
Buddy explains!

The straight part
We know that "wide open" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case wide open = yawning.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 YAWNING mean?
YAWNING verb- To open the mouth widely and take a long, rather deep breath, often because one is tired or bored, and sometimes accompanied by pandiculation.
- To say while yawning.
- To present a wide opening.
- To open the mouth, or to gape, through surprise or bewilderment.
- To be eager; to desire to swallow anything; to express desire by yawning.
- The action of the verb yawn.
- That yawns or yawn.
- Wide open.