The most common and most likely answer to this crossword clue is the 7 letter word EXTREME
I've seen this crossword clue in The Times
E
X
T
R
E
M
E
More clues leading to the result EXTREME
- Strict unopened communication about the setter
- Outermost part of Exeter sprawling across motorway
- Serious retired actor of old entertained millions
- Former actor holding opening of Macbeth to be over the top
- Record possibly first released by later engineers
- Too much here to be taken out of context — remember?
- Radical former partner Mike wearing lime perhaps
- Old chestnut, say, about male that is very severe
- Very strict time kept by old regiment
- Very high mass in timber, might you say?
Buddy explains!

The straight part
We know that "Very strict" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case very strict = extreme.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 EXTREME mean?
EXTREME noun- The greatest or utmost point, degree or condition.
- Each of the things at opposite ends of a range or scale.
- A drastic expedient.
- Either of the two numbers at the ends of a proportion, as 1 and 6 in 1:2=3:6.
- Of a place, the most remote, farthest or outermost.
- In the greatest or highest degree; intense.
- Excessive, or far beyond the norm.
- Drastic, or of great severity.
- Of sports, difficult or dangerous; performed in a hazardous environment.
- Ultimate, final or last.
- Extremely.