[countable, usually singular] beginning (of something) the time when something starts; the first part of an event, a story, etc. We're going to Japan at the beginning of July. She's been working there since the beginning of last summer. We missed the beginning of the movie. Let's start again from the beginning. The birth of their first child marked the beginning of a new era in their married life. I've read the whole book from beginning to end and still can't understand it.