The most common and most likely answer to this crossword clue is the 12 letter word OCTOGENARIAN
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More clues leading to the result OCTOGENARIAN
- Old person’s gone off with raincoat
- Go into care managed by an oldie
- New coronation age deprived of old Queen? She is such a one
- Veteran’s gone out in shabby raincoat
- Old man‘s gone with raincoat undone
- . Brief congregational disturbance after the removal of a good senior citizen
- In years, having four scores to settle, try retaliating, organising action near...
- Senior citizen’s retina can go awry along with edge of optic-nerve
Buddy explains!

The straight part
We know that "Senior citizen" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case senior citizen = octogenarian.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 OCTOGENARIAN mean?
OCTOGENARIAN noun- One who is between the age of eighty and eighty-nine, inclusive.
- Being between the age of 80 and 89, inclusive
- Of or relating to an octogenarian