Fido (origin and meaning)

I think a fido is a coin with error: a coin with a minting error

but also seems to be a Mid-20th century Acronym formed from freaks, irregulars, defects, and oddities, can anybody help with the date in which was first used?

any other meanings?

Acronym finder supplies a number of other uses, and verifies freaks, etc.:
[Dead link removed - ed]
I haven't found a date of first use yet.

A name for a dog of course. I do find "fido" the acronym in Webster's 1974 Collegiate Ed, which means it's been around for a good while. Coincidentally, I've experienced great difficulty in determining dates words first used; any followup on this very subject appreciated--DH