I’m too old to know what Phineas and Ferb is, but when I was young I used to love knowing obscure words like:

• The indent between your upper lip and your nose is called the philtrum (more commonly known now because of piercings

• The recess on the bottom of a wine bottle is called a punt.

• The infinity symbol (like a sideways 8) is a lemniscate

• The cap on the pointy end of an umbrella, or any other tubular thing (including a pencil) is called a ferrule

• The space between your eyebrows is your glabella

Etc. Anyway, aglet was one of those. I was always so happy when I had an opportunity to use one (“Oh, man, my aglet broke!”).