irisation

noun

iris·​ation

ˌīrə̇ˈsāshən

plural -s

1

: the act or process of making iridescent

the irisation of a culture plate by developing bacteria

2

: iridescence

irisations in a cloud are evidence that it is composed of water droplets

—D. W. Perrie

in the area of the sun beautiful irisations may occur

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