The most common and most likely answer to this crossword clue is the 6 letter word STODGY
I've seen this crossword clue in The Daily Telegraph
S
T
O
D
G
Y
More clues leading to the result STODGY
- Uninspired old head of BBC grasping pen? On the contrary
- Very dull dirty dog put in enclosure
- Dense, sticky hot dogs regularly occupying enclosure
- Dirty place houses nothing chief exec finds dull
- Heavy dog sadly kept in enclosure
- Dull old BBC boss found in place of debauchery
- Dog went mad in pen? That’s tedious!
- Boring grand party over in swine’s home
- Somewhat tedious or dull generating yawns initially
- Heavy overdose by heartless guy on street
Buddy explains!

The straight part
We know that "Somewhat tedious or dull generating yawns" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case somewhat tedious or dull generating yawns = stodgy.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 STODGY mean?
STODGY adjective- (of food) Having a thick, semi-solid consistency; glutinous; heavy on the stomach.
- Dull, old-fashioned.
- Badly put together.