A more thorough explanation:

A suppletory oath is a type of oath that is taken when there is a lack of evidence or information about a particular matter. It is a solemn declaration made by a person that is considered to be true and binding. The person taking the oath invites punishment if the statement is untrue or the promise is broken. The legal effect of an oath is to subject the person to penalties for perjury if the testimony is false.

For example, if a witness in a court case does not have enough evidence to prove their testimony, they may take a suppletory oath to attest to the truth of their statement. This type of oath is also used in situations where there is a lack of documentation or evidence to support a claim.

Another example of a suppletory oath is when a person takes an oath of office without having all the necessary documents or qualifications. The suppletory oath is taken to fill in the gaps and ensure that the person is still able to perform their duties.

In summary, a suppletory oath is a type of oath taken when there is a lack of evidence or information about a particular matter. It is a solemn declaration made by a person that is considered to be true and binding.