Definition

1. Noun:
   • Water flea: A common name for very small, aquatic crustaceans, especially of the genus Daphnia, that swim with a jerky, hopping motion. They are often found in ponds and are an important food source for fish.

Usage Examples

• Noun:
  • Rận nước là thức ăn quan trọng cho cá bột. (Water fleas are an important food source for fry.)
  • Chúng tôi quan sát rận nước dưới kính hiển vi. (We observed the water flea under a microscope.)
  • Ao có nhiều rận nước thường có nước khá sạch. (A pond with many water fleas often has quite clean water.)

Advanced Usage

• In scientific and biological contexts, "rận nước" most specifically refers to organisms in the order Cladocera, with being a well-known genus.
  • Nghiên cứu này theo dõi vòng đời của rận nước Daphnia magna. (This study tracks the life cycle of the water flea Daphnia magna.)

Variants and Related Words

• Bọ nước: A more general term for small aquatic insects or bugs, which may sometimes be used interchangeably with "rận nước" in casual speech, though it is less scientifically precise.

Synonyms

• Water flea: The direct and most accurate translation.
• Daphnia: The scientific genus name, often used as a common name in English.

Notes on Usage

• "Rận nước" is a compound noun. The word "rận" alone means "louse," but in this biological context, the compound specifically refers to the aquatic crustacean and not a parasite.
• It is primarily used in scientific, educational, or hobbyist contexts (e.g., aquaculture, aquarium keeping).