firefly

Everyday

1. A small flying beetle whose tail glows with a soft light at night. tree →
2. Another name some people use for a glow-worm or any insect that makes its own light. tree →

In the lessons

In science lessons fireflies show bioluminescence: a living thing making light by a chemical reaction in its body, with almost no heat. In stories they stand for summer evenings, magic and wonder. Phrases: «catch fireflies», «a jar of fireflies», «fireflies blink/flash».

Examples

• We watched fireflies blinking over the meadow on a warm summer night. tree →
• A firefly makes light without getting hot. tree →
• Fireflies flash in patterns to find a partner. tree →
• My little brother caught a firefly in his hands and then let it go. tree →
• Fireflies are not flies at all; they are beetles. tree →
• In the story, the lost girl followed the fireflies home. tree →
• If you put fireflies in a jar, make holes in the lid and free them soon. tree →
• Great suns spurted fire about, splendid fireflies flew into the blue air, and everything was reflected in the clear, calm sea beneath. tree →

Note

Plural: fireflies (y → ies). Called «lightning bugs» in much of the USA; in the UK, Australia and New Zealand the common glowing insects are glow-worms. Trap: despite the name, a firefly is a beetle, not a fly, and it has nothing to do with fire. Countable.