Iridescent
Etymology
Coined in the eighteenth century from Latin "iris" ("rainbow"), which came from Greek "iris" (the rainbow, personified as the goddess Iris), plus the suffix "-escent" ("becoming, tending toward"). The word names surfaces that seem to shimmer with rainbow-like colors as they catch the light.
adjective · /ir-ih-DES-unt/
Showing shifting, luminous colors that change with the angle of view, like a rainbow.
What it names
The word for that shimmering play of color across a surface — soap bubbles, oil on water, a beetle’s shell.
Example
The hummingbird’s throat flashed iridescent green and violet as it turned.
Related idea
Opalescent suggests the milky, shifting glow of an opal; iridescent suggests brighter, rainbow-like color that changes with the light.