iridium
part of speech
noun (iridium — uncountable)
meaning for a pupil
A very hard, heavy, silvery metal, a chemical element (symbol Ir), which hardly rusts or wears away. tree →
sense in the lessons
In science lessons iridium is famous because a thin layer rich in iridium around the world, laid down about 66 million years ago, helped scientists infer that a huge asteroid hit the Earth when the dinosaurs died out. It is used in spark plugs and pen nibs. Phrases: «iridium layer».
examples
- Iridium is one of the densest metals on Earth. tree →
- Scientists found a layer of iridium in rocks all over the world. tree →
- That iridium came from an asteroid. tree →
- Iridium hardly ever rusts. tree →
- The tip of the fountain pen is made with iridium. tree →
note
Uncountable. Symbol Ir. Named from «iris» (rainbow) because its salts are many colours.
Trees and pragmatics
Every meaning and example of «iridium» parsed by Mova, each sentence with its dependency tree and frames.