This is the 10986th most frequent Turkish word.
dirseğinin
"Dirseğinin" means "of your elbow" in English.
In this context, "dirseğinin" is used to specify the body part (elbow) experiencing pain.
Dirseğinin ağrısı mı geçmedi?
Hasn't the pain in your elbow gone away?
The phrase "dirseğinin darbesi" refers to the blow/hit made using the elbow.
Boks sırasında dirseğinin darbesi rakibini yere düşürdü.
During boxing, the impact of your elbow caused your opponent to fall.
Here, "dirseğinin" is a possessive form of "dirsek" (elbow) indicating the elbow belonging to the addressed person.