laser

Everyday

1. A machine that makes a very narrow, strong beam of light of one colour. tree →
2. The beam itself. tree →

In the lessons

In science, lasers are used in barcode scanners, eye surgery, measuring distances, cutting metal and in light shows. In safety, never shine a laser pointer at someone's eyes, at animals, cars or planes — it can blind people. Phrases: «laser pointer», «laser beam», «laser printer», «laser tag».

Examples

• The shop scanner uses a laser to read barcodes. tree →
• The teacher pointed at the screen with a laser pointer. tree →
• Never shine a laser in anyone's eyes. tree →
• Doctors can fix eyes with lasers. tree →
• We played laser tag at the party. tree →
• A laser beam is very straight and narrow. tree →

Note

Countable: lasers. It was made from the first letters of a long phrase, so it is an «acronym». Shining lasers at aircraft is dangerous and against the law.