* Claim can be used as a noun to refer to a statement that something is true, especially when it is disputed.
* Example: "Her claim to the throne was contested by her rival."
* Claimant is a noun that refers to a person who makes a claim, especially a legal claim.
* Example: "The claimant filed a lawsuit against the insurance company."
The choice between the two depends on the context and what you want to emphasize.