The most common and most likely answer to this crossword clue is the 8 letter word MATRONLY
I've seen this crossword clue in The Times
M
A
T
R
O
N
L
Y
More clues leading to the result MATRONLY
- Staid old lady, but about to relax at the front
- Dull king, nothing but dignified as a woman
- Like distinguished lady from Tyrol man upset
- Rather fat runner, say, runs — just
- Stout, middle-aged trader cleared out just after mum
- Month in which model gets just a bit staid and plumpish
- Spoil over time, just like an old woman
- Dull queen just like a portly old soul?
- Tram moving just like a married woman...
- Friend shortly runs single rounder after children
Buddy explains!

The straight part
We know that "Stout, middle-aged" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case stout, middle-aged = matronly.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 MATRONLY mean?
MATRONLY adjective- In the capacity of a matron; serving as a housekeeper or head nurse.
- Exuding the authority, wisdom, power, and intelligence of an experienced woman.
- Having the appearance of a mature woman, often of larger physical stature and somewhat unkempt or dowdy.
- In the manner of a matron.