The answer to your problem is DENT.
dent
i think it is dent
Wikipedia
That is the correct spelling of the word depression (an indentation, or a gloomy psychological state).
Another word for depression or indentation is "concavity." Concavity refers to a surface that curves inward or has a depressed area. It is commonly used in mathematics and geometry to describe the shape of a curve or surface that is curved inward rather than outward.
dent
The base word of "indentation" is "indent".
The word 'depressed' is the past participle, past tense of the verb to depress. The past participle of the verb also functions as an adjective.The abstract noun forms of the verb to depress are depression and the gerund, depressing.The noun depression is an abstract noun as a word for a state of sadness and low spirits.The noun depression is a concrete noun as a word for an indentation in something physical.
There was one word that would fit the meaning of indentation and desperation. This word would be 'rash' and also fits the four letter length.
abyss, chasm, crater, dent, depression, dimple, excavation, grave, gulf, hell, hollow, indentation, mine, perforation, pothole, puncture, shaft, tomb, trench, well
The word dimple is a noun meaning a slight indentation. Although it can refer to any indentation on any surface, it is usually used in reference to the physical trait of having a natural indentation somewhere on the human body, commonly on the cheeks of the face.
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