Can people use past tenses in defining a term?

[cubezero3]

Hello, everyone.

I came across this definition a moment ago. I thought only present tenses can be used in the definition of a term, because a definition itself means what is says is always the case.

account day(UK) The day on which all transactions made during the previous account at the stock exchange had to be settled (hence, settlement day).

The Penguin International Dictionary of Finance

I'd like to hear your opinions.

Many thanks

Richard

[Rover_KE]

The definition quoted leads us to think that account day (UK) is a term no longer in use.

If it is still used, had should be has.

Rover