General:
* Someone
* A person
* An individual
* A soul
* One
* A being
Informal:
* A fellow
* A chap (British)
* A dude
* A guy
* A gal
* A person
Specific to importance/status:
* An authority
* An expert
* A leader
* A celebrity
* A notable figure
Specific to action:
* A participant
* A contributor
* A volunteer
* An actor
* A performer
Specific to feeling/emotion:
* A loved one
* A friend
* A confidant
* A victim
* A witness
To choose the best synonym, consider the following:
* Formal vs. informal context: Use more formal synonyms in formal writing.
* Specific meaning: Choose a synonym that accurately reflects the person's role or status.
* Desired tone: Some synonyms carry positive or negative connotations.
For example, "someone" is a neutral synonym, while "an authority" suggests a person with expertise.