radical
part of speech
adjective (radical, more radical, most radical); noun (a radical, radicals)
meaning for a pupil
1) Very big and basic, changing the most important parts of something: a radical change. tree →
2) Having very strong or extreme ideas about how society or politics should change. tree →
3) (noun) A person with extreme political ideas. tree →
4) (maths) To do with roots, such as the square root sign √, which is called the radical sign. tree →
5) (science) A free radical is an atom or group of atoms with an unpaired electron, which reacts easily. tree →
6) (slang, US, dated) Really cool or amazing — "Radical, dude!" tree →
sense in the lessons
In everyday life, a radical change is a huge one, like moving to a new country. In politics and history lessons, radicals were people who wanted big changes fast, sometimes peaceful, sometimes violent. In maths, the radical sign √ shows a square root: √16 = 4. In stories, a "radical" character challenges how things are. Phrases: radical change, radical idea, radical sign, free radical.
examples
- The new head teacher made radical changes to the timetable. tree →
- Moving from the city to a farm was a radical change for our family. tree →
- Some radicals wanted to get rid of the king. tree →
- In maths, the radical sign √ means "square root of". tree →
- √25 is called a radical expression, and it equals 5. tree →
- "That skateboard trick was radical!" shouted the surfer dude. tree →
- Her idea to have no homework at all seemed radical to the teachers. tree →
note
"Radical" comes from Latin "radix", meaning root — so a radical change goes right to the roots. In maths, √ is the radical sign: √9 = 3 because 3 × 3 = 9. The slang meaning "cool" is old-fashioned 1980s surfer talk, now mostly a joke. Adverb: radically.
Trees and pragmatics
Every meaning and example of «radical» parsed by Mova, each sentence with its dependency tree and frames.