When you alphabetize things, you put them in A-to-Z order — the same order as the letters of the alphabet. Teachers alphabetize class lists by family name; libraries alphabetize books; a phone can alphabetize your contacts with one tap. If two words start with the same letter, you look at the next letter, and so on. American English writes alphabetize; British English often writes alphabetise. Everyday speech also says put in alphabetical order, which means the same thing and is a little more common outside offices and computers. It is a practical, slightly school-and-office word, not an emotional one.