The most common and most likely answer to this crossword clue is the 8 plus 7 letter word ELECTRIC BLANKET
I've seen this crossword clue in The Times
E
L
E
C
T
R
I
C
B
L
A
N
K
E
T
More clues leading to the result ELECTRIC BLANKET
- Warmer kind of blue and white escort's coat
- . Household device for re-heating kippers
- Playing netball and cricket keeps English warmer
- For a warm layer, choose grandma’s second patterned cable knit
- One might go on before one goes off
- Current employer confined to bed
- This may prove a comfort to one who’s just retired
- Coverage for retirement dependent on current supply
- Powerful contributor towards retirement?
- It makes a powerful contribution for a comfortable retirement
Buddy explains!
The straight part
We know that "Warmer" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case warmer = electric blanket.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.