The most common and most likely answer to this crossword clue is the 14 letter word CLAUSTROPHOBIA
C
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A
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A
More clues leading to the result CLAUSTROPHOBIA
- Being in fear
- . Santa’s terrible habit, poor thing, when cooped up?
- Santa’s disgusting habit – poor reaction to getting stuck in chimney?
- Fear of being shut in front of cockpit with a BA pilot – hours wasted
- Laborious patch in puzzle engenders feeling of being badly stuck in corner?
- Irrational fear of being stuck in the lift with Father Christmas?
Buddy explains!

The straight part
We know that "Irrational fear" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case irrational fear = claustrophobia.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 CLAUSTROPHOBIA mean?
CLAUSTROPHOBIA noun- The fear of closed, tight places.