The most common and most likely answer to this crossword clue is the 6 letter word SAFEST
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More clues leading to the result SAFEST
- Most secure small 23 in disorder
- Organises a festival involving most sound
- Most unadventurous Rio carnival, possibly
- Salvation Army with good person holding case for flute that makes most sound
- Most conservative party in Pretoria, possibly?
- In drunken sets a female should be most cautious
- . Most secure seats set to accommodate foreigners, chiefly
- South American party least exposed to danger
Buddy explains!

The straight part
We know that "Most secure" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case most secure = safest.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 SAFEST mean?
SAFEST adjective- Not in danger; out of harm's reach.
- Free from risk.
- Providing protection from danger; providing shelter.
- When a batter successfully reaches first base, or when a baserunner successfully advances to the next base or returns to the base he last occupied; not out.
- Properly secured.
- (used after a noun, often forming a compound) Not susceptible to a specified source of harm.
- Great, cool, awesome, respectable; a term of approbation, often as interjection.
- Lenient, usually describing a teacher that is easy-going.
- Reliable; trusty.
- Cautious.
- Of a programming language, type-safe or more generally offering well-defined behavior despite programming errors.