The most common and most likely answer to this crossword clue is the 8 letter word YEASTIER
I've seen this crossword clue in Financial Times
Y
E
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Buddy explains!
The straight part
We know that "more /redolent of Marmite/redolent of Marmite" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case more /redolent of marmite/redolent of marmite = yeastier.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 YEASTIER mean?
YEASTIER adjective- Having or resembling yeast.
- Foamy and frothy.
- Emotionally bubbling over (as with exuberance)
- Trivial.