1. Call (as in a phone call): The noun form is simply "call" itself.
* Example: "I received a call from my mother."
2. Call (as in a summons or request): The noun form is also "call".
* Example: "The teacher made a call for volunteers."
3. Call (as in a shout or cry): The noun form is "call".
* Example: "The birds gave a call in the morning."
4. Call (as in a profession or occupation): The noun form is "calling".
* Example: "She found her calling in nursing."
5. Call (as in a name or title): The noun form is "name" or "title".
* Example: "He answered to the name of John."
The best way to figure out which noun is correct is to consider the context of the sentence.