The most common and most likely answer to this crossword clue is the 7 letter word RETARDS
I've seen this crossword clue in The Daily Telegraph
R
E
T
A
R
D
S
More clues leading to the result RETARDS
- Concerned with time machine forgetting one decelerates
- End dimensions’ limits admitting time slows down
- Back case for doctors accepting time slows down
- Spacecraft, deprived of one group of engineers, initially slows down
- Phenomenal roadster loses tempo, finally slows down
- Slows down sailor in Reds
- Slows down manic traders
Buddy explains!
The straight part
We know that "decelerates" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case decelerates = retards.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 RETARDS mean?
RETARDS noun- Retardation; delay.
- A slowing down of the tempo; a ritardando.
- A person with mental retardation.
- A person or being who is extremely stupid or slow to learn.
- To keep delaying; to continue to hinder; to prevent from progress
- To put off; to postpone.
- To be slow or dilatory to perform (something).
- To decelerate; to slow down.
- To stay back.