Alphabetically means arranged or organized in the order of the letters in the alphabet, from A to Z. When you look up a word in a dictionary, you find it alphabetically: all the words starting with A come first, then B, then C, and so on. Within each letter section, the second letter determines the order, then the third, and so forth. So “apple” comes before “apricot” because “p” comes before “r” in the alphabet.

Libraries organize fiction books alphabetically by the author's last name, which makes finding a specific book much easier than searching randomly through thousands of titles. Your teacher might call on students alphabetically by last name, starting with Anderson and ending with Zimmerman. Class rosters, phone books, indexes at the back of textbooks, and contact lists on phones all use alphabetical order because it's a system everyone understands.

Before computers, organizing information alphabetically was one of the most important ways humans kept track of knowledge. Even today, when search functions can find things instantly, alphabetical order remains useful because it's predictable: you always know exactly where to look.