This is the 2476th most frequent Turkish word.
konuşmasının
"His/her/its speech" or "of his/her/its speech."
Here, "konuşmasının" derives from "konuşma" (speech) and serves as a possessive and genitive noun indicating 'his speech'.
Onun konuşmasının ardından herkes alkışladı.
After his speech, everyone applauded.
This indicates the pace of someone's speech, which is a possessive genitive construction indicating ownership of the 'pace' as related to the speech.
Konuşmasının hızını biraz düşürdüğünde herkes daha iyi anladı.
When he slowed down his talking pace a little, everyone understood better.
Here the word refers to the speech itself, indicating the act or content of the speaking delivered by the individual.