Credit to this video for explaining the concept of phrasing to me.

A phrase is a succession of notes that form a distinctive sequence in a musical composition.

Most Western electronic and pop music is structured into 16 or 32 beat phrases. When mixing, we want to make sure these phrases line up to create a seamless mix.

How can you spot phrases? Well, there are a few common clues you can look for while listening to a track that will indicate either the start or end of a phrase: drum fills at the end of the phrase, a big crash at the beginning of a new phrase, or new instruments being introduced as the song continues to play.

In most DJ software, there is a counter that indicates the current phrase, bar, and beat. This allows you to stay on top of the track structure even when you are distracted and not paying full attention.

You want to make sure your phrases match during your mix. When you’re bringing in your new track, you want to make sure you’re bringing it in at the start of a phrase and that it’s in time with the phrase of the currently playing track.