Alga

Part of speech: noun

Pronunciation: /ˈæl.ɡə/

Definitions

1. A group of simple aquatic organisms that perform photosynthesis and can exist in both single and multicellular forms found in various water habitats
2. Organisms that primarily conduct photosynthesis in aquatic settings, varying from single-celled to complex multicellular structures essential for ecosystem health
3. A diverse group of photosynthetic organisms found in water, including both unicellular and multicellular varieties that play a crucial role in marine and freshwater ecosystems

Etymology: "Alga" is a Latin noun meaning seaweed or a water plant of this kind, and English took it over directly without changing its form. Its ancestry is not known with certainty, and the Latin word had no native English relative to share its sound. Because English borrowed the word whole, it kept its Latin shape, so the plural in English is "algae," which follows the Latin pattern of a first-declension noun. That plural has become the normal form in modern English, and many speakers treat "alga" as the singular of a mass term, though "algae" is commonly used for the whole group of organisms.

Synonyms: seaweed, kelp, phytoplankton