Unfamiliar word section 

By what standard are we saying a word is unfamiliar, specifically, but what time period?  Contemporary to publication or time the article is written?  If the former, I think 'spiff' may not be so unfamiliar.  I won't swear to it, but it came across as contemporary slang like in line with Archie speaks.  I wouldn't be surprised if it's related to, even a basis for, 'spiffy'.