The most common and most likely answer to this crossword clue is the 7 letter word PADLOCK
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K
More clues leading to the result PADLOCK
- Something to secure flat piece of hair
- Within walls of park, a bitter brought over for one of those on the gate?
- One way to secure former standing within group
- Old man left in port area as security measure
- Stuff with hair — it’s for reasons of safety
- Security device gets secretary and student in place of those accused
Buddy explains!

The straight part
We know that "security measure" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case security measure = padlock.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 PADLOCK mean?
PADLOCK noun- A detachable lock that can be used to secure something by means of a sliding or hinged shackle
- To lock using a padlock.