Answer:
Lighting is referring to the object.
Lighting Design refers to the arrangement of the Lighting objects.
Lighting objects are numerous and diverse.
sconce/wall fixture
ceiling fixture
chandelier
post lantern
gas lantern
pendant/hanging fixture
track
recessed can
spot
floor lamp
table lamp
etc., etc.,
Lighting Design does go far beyond the arrangement, there are many other factors to consider when working with a lighting design, such as the heat a certain type or number of lights will emit as well as the color tone and how the placement of each light will affect the color palette of the room and the balance of the floor plan.