A pair of primitive excretory (waste-removing) organs found in some simple animals, particularly certain worms.
From Greek 'diplos' (double) + 'nephros' (kidney) + '-idia' (plural suffix). A biological term describing the paired kidney-like structures in organisms without true kidneys.
Ancient worms don't have kidneys like we do—instead they have these paired 'double kidneys' that filter waste. It's a reminder that life solved the 'getting rid of waste' problem millions of years before humans evolved!
Complete word intelligence in one call. Free tier — 50 lookups/day.