Threadbare

As I said the other day, if you have a collection of Latin roots in your head, you can often be successful at picking apart words that momentarily interest you. But sometimes you are led astray through no fault of your own.

The word of the day yesterday was "affiliate", and of course the first syllable is our old friend "ad-", "to", mutated by its proximity to the fricative "-f-". The rest, though. All I could come up with was "filament", from Latin "filum", "thread", and so something to which you are affiliated must be...something you are...tied to...with thread....

Okay, that's obviously nonsense. But I couldn't get past the "filum" association. When I got home and looked it up, I could have slapped myself, because it was so obvious in retrospect: the word was related not to "filament" but to "filial", because Latin "filius" means "son", the verb "affiliare" means "to adopt as a son", and therefore to affiliate yourself with an organization means to be (figuratively) adopted by them.