Bursts of liquid spraying or scattering, or areas of bright color that stand out against a background.
From Middle English 'splash,' likely imitative in origin (the word imitates the sound liquid makes); first recorded in the 1600s as an onomatopoeia.
Splash is a perfect example of onomatopoeia—the word literally sounds like what it describes, and your mouth even makes a 'sp' sound that mimics the spray action, which is why onomatopoeia words are often remembered instantly.
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