Antonyms come in three flavours

Gradable antonyms sit on a scale like hot and cold, complementary ones exclude each other like alive and dead, and relational ones need each other like teacher and student.

#words #antonym #grammar #language

'Flammable' and 'inflammable' mean the same

Inflammable comes from inflame, not from a negative prefix. Safety officials pushed flammable to stop deadly confusion.

'Awful' once meant awesome

Both words came from awe. Awful drifted to terrible while awesome kept the wonder, splitting a single idea in two.

'Up' and 'down' break the rules

Slow down and slow up mean the same thing. Idioms often ignore the logic of their own antonyms.