There are times when dismal and gloomy may be used interchangeably:
- Christmas was gloomy without the children.
- Christmas was dismal without the children.
In the above examples, the two words mean sad/miserable/depressing. You can also use both words to describe dark, depressing weather:
- We had such dismal/gloomy weather. We stayed at home and binge-watched Big Bang Theory.
However, there are times dismal and gloomy collocate differently and are not interchangeable:
- Oh, you have invited Bob? He’s so gloomy these days, he’ll spoil the party.
In this example, Bob is described as feeling down/depressed. Dismal is not the right word to use in this context.
On the other hand, the word gloomy is not used in the following contexts:
- Our attempt to break into the Asian market was a dismal failure.
- We were so excited to see Mariah Carey, but she gave a dismal performance.
In these examples, dismal means unsuccessful/low quality.
If you would like to learn more about what collocations are, read Collocations List with meanings and examples.