A more thorough explanation:

Definition: Infra annum (in-frə an-əm), adv. [Law Latin] Under a year; within a year.

Example: The warranty for the new car covers any defects that may arise infra annum from the date of purchase.

Explanation: In this example, "infra annum" means that the warranty will cover any defects that occur within a year from the date of purchase. This means that if any issues arise with the car within the first year, the warranty will cover the cost of repairs or replacement.