Your body becomes blurred, shifting and wavering to all who can see you. For the duration, any creature has disadvantage on attack rolls against you. An attacker is immune to this effect if it doesn't rely on sight, as with blindsight, or can see through illusions, as with truesight.
The 2024 Player’s Handbook revised many spells, and the SRD 5.2 carries the new text. What changed from the 2014 version above:
Same level, casting time, range, components, duration and dice; the text is reworded for the 2024 rules glossary.
Casting time
Action
Range
Self
Components
V
Duration
Concentration, up to 1 minute
School
Illusion
Level
2
Classes
Sorcerer, Wizard
Tags
concentration
Your body becomes blurred. For the duration, any creature has Disadvantage on attack rolls against you. An attacker is immune to this effect if it perceives you with Blindsight or Truesight.
2024 version from the SRD 5.2. Most tables settle on one edition, so check which one yours uses.