Noun:
* The highness or lowness of a sound: "The singer's pitch was perfect."
* A proposal or suggestion: "The company pitched their new product to investors."
* A black, sticky substance used to make tar: "They used pitch to seal the roof."
* A place for camping or tents: "We set up our tent at the campground pitch."
Verb:
* To throw or toss something: "The pitcher pitched the ball to the batter."
* To offer or propose something: "The team pitched their idea to the board."
Adjective:
* Very steep or sharp: "The road was a pitch-black incline."
Therefore, the part of speech for "pitch" depends entirely on the context in which it's used.