Final answer:
Availability float refers to the delay between depositing a check and the funds becoming accessible in an account, relevant to banking and finance.
Step-by-step explanation:
Availability float is a term used in banking and finance to describe the time difference between when a check is deposited and when the funds are available in the payee's account. This period is when the bank is processing the check and the payee cannot yet access the funds. The concept of proper time, although related to measuring intervals, is a concept from physics that describes the time interval measured by an observer where two events occur at the same location. However, in the context of availability float, it pertains to the delay in the banking process. The availability float can cause inconvenience for individuals or businesses that need to rely on a timely update of their account balances for managing finances.