This is the 87th most frequent Marathi word.
कस
Edge, quality, or essence.
In this sentence, the word 'कस' is used to ask for the method or manner in which a task was completed.
तू हे काम कस केलंस?
How did you do this work?
Here, 'कस' is used to inquire about the condition or state of events.
कस काय चाललंय?
How is everything going?
In this usage, 'कस' is part of 'कसरत', referring to exercise or strenuous activity, showcasing how words in Marathi are compounded.