Dynamic range is the space between the quietest useful detail and the loudest peak in a mix.
Definition
Musical contrast you can measure
Dynamic range describes how much level contrast exists inside a track. Wide dynamic range leaves more room between soft details and loud hits. Narrow dynamic range keeps the signal consistently dense.
Neither is automatically better. A sparse acoustic track needs different contrast than a modern club master. The useful question is whether the range supports the arrangement.
Processing
How dynamics get reduced
Compression, saturation, clipping, and limiting all reduce dynamic range in different ways. A single processor may be subtle, but a full chain can remove more movement than expected.
The problem usually appears late, when the master is loud but no longer breathes. Metering each stage makes that drift easier to catch.
Check
Compare movement, not only level
Level-match your references and listen for how drums recover, how vocals sit between lines, and whether drops still feel bigger than verses.
If your mix has the same LUFS as the reference but less movement, the issue is probably dynamics rather than loudness target.