The most common and most likely answer to this crossword clue is the 4 letter word SIGH
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More clues leading to the result SIGH
- Express regret, with vision falling short.
- Sound despairing when spectacle fails to end
- Keeling over, hot servicemen expire, sadly
- Sound sad, vision being cut short
- Firstly, settle in good home and express relief
- Exude an air of sadness
- Servicemen upset, hearts show dejection
- Audible expression of sadness, in a sense, cut short
- With time passing, great number sound regretful
- Faculty cut, oh dear
Buddy explains!

The straight part
We know that "show dejection" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case show dejection = sigh.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 SIGH mean?
SIGH noun- A deep, prolonged audible inhale and exhale of breath; as when fatigued, frustrated, grieved, or relieved; the act of sighing.
- Figuratively, a manifestation of grief; a lament.
- A person who is bored.
- To inhale a larger quantity of air than usual, and immediately expel it; to make a deep single audible respiration, especially as the result or involuntary expression of fatigue, exhaustion, grief, sorrow, frustration, or the like.
- To lament; to grieve.
- To utter sighs over; to lament or mourn over.
- To experience an emotion associated with sighing.
- To make a sound like sighing.
- To exhale (the breath) in sighs.
- To express by sighs; to utter in or with sighs.
- An expression of fatigue, exhaustion, grief, sorrow, frustration, or the like, often used in casual written contexts.