Illuminate

v.hopeful, thoughtfuleveryday

Meaning 1

To supply light that makes a place or object visible.

Reach for it when describing deliberate lighting for sight, safety, or display

Low lamps illuminate the path without washing out the night sky.

everyday
light
the physical act needs the plainest available verb
not when Light can mean ignite and carries less sense of revealing a whole scene.
warm
brighten
added light also improves the mood or appearance
not when Brighten can lift spirits without making details easier to see.
professional
floodlight
powerful directed lamps cover a large exterior area
not when Floodlight is far too intense for subtle or protective illumination.

To make an idea, event, or pattern easier to understand.

Reach for it when praising evidence or explanation that reveals useful meaning

The letters illuminate how the two workshops shared tools during the strike.

everyday
explain
someone states how or why something works
not when An explanation may be complete but dull, while illuminate suggests gained insight.
professional
clarify
confusion should be directly removed
not when Clarify lacks the discovery and visual metaphor of illuminate.
professional
demonstrate
evidence visibly proves or displays the point
not when Demonstrate is stronger about proof and weaker about interpretation.
formal
elucidate
a difficult point needs exact scholarly explanation
not when Elucidate is bookish and cannot describe physical light.
literary
reveal
hidden evidence or meaning comes into view
not when Reveal emphasizes disclosure, not the fuller understanding that follows.

illuminate the path
Recessed lamps illuminate the path beside the canal.
illuminate the subject
Two household ledgers illuminate the subject better than the official summary.
help illuminate
The restored plan may help illuminate why the entrance faces east.
illuminate the room
A row of shaded windows will illuminate the room without creating glare.

The definition and the example on this page are written here. The dictionaries above ground which meaning is being described, not the wording.