This is the 12747th most frequent Turkish word.
istemeyen
"Not wanting"
'İstemeyen' modifies 'öğrenci' (student), acting as an adjective to describe a specific student having a particular feeling or attitude.
İstemeyen öğrenci, ek çalışma yapabilir.
A student who does not wish can do additional work.
In this sentence, 'istemeyen' qualifies 'çocuk' (child), specifying which child the action is about, forming a dependent clause defining the child.
Yemeği istemeyen çocuk başka yemek istedi.
The child who does not want the meal asked for another.
Here, the word 'istemeyen' is used as an adjective describing 'kişiler' (individuals), implying a quality pertaining to the individuals who do not wish to engage in the mentioned activity.