The most common and most likely answer to this crossword clue is the 4 letter word CALM
C
A
L
M
More clues leading to the result CALM
- Windless California at beginning of May
- Composed about fifty minuets initially
- Still, a reticent person needs a change of heart
- Serenity found amid diabolical mayhem
- River surrounding Lake Placid
- Assured piece of topical mimicry
- Quiet, silent type has change of heart
- Learner in academic stream still
- Cool 100 prime pieces of salami
- It’s quiet in typical museum
Buddy explains!

The straight part
We know that "Windless" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case windless = calm.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 CALM mean?
CALM noun- (in a person) The state of being calm; peacefulness; absence of worry, anger, fear or other strong negative emotion.
- (in a place or situation) The state of being calm; absence of noise and disturbance.
- A period of time without wind.
- To make calm.
- To become calm.
- (of a person) Peaceful, quiet, especially free from anger and anxiety.
- (of a place or situation) Free of noise and disturbance.
- (of water) with few or no waves on the surface; not rippled.
- Without wind or storm.