caustic

Everyday

1. Able to burn or eat away skin and other materials by a chemical action, as in «caustic soda». tree →
2. Cruel and sharp in a clever, sarcastic way, as in «a caustic remark». tree →

In the lessons

In science and safety lessons, caustic chemicals such as drain cleaner, oven cleaner and caustic soda (sodium hydroxide) are strong alkalis that burn skin and eyes: never touch them, keep them locked away, and read hazard labels. In stories, a caustic comment tells the reader that a character is being bitingly unkind.

Examples

• Caustic soda can burn your skin. tree →
• The drain cleaner bottle had a caustic warning sign. tree →
• Wear gloves and goggles with caustic chemicals. tree →
• She made a caustic remark about his drawing. tree →
• The critic wrote a caustic review of the film. tree →
• Keep caustic cleaners out of children's reach. tree →
• His caustic jokes hurt people's feelings. tree →

Note

Adjective. Said «KAWS-tik». Science note: caustic usually means a strong alkali (base), not an acid, but both can burn. If a caustic chemical gets on skin, rinse with lots of water and get an adult or call for help.