- The definition of appalling is something that is so bad that it causes people to be shocked, get angry about it or be terrified by it.
The grim condition of people in poverty-stricken areas is an example of an appalling condition.
- Present participle of appall.
(comparative more appalling, superlative most appalling)
- Horrifying and astonishing.
- That was an appalling waste of money.
- Not to be confused with appealing.
Variant of appal