Emission and omission are easily confused words.
The spell-check application of most word processing software programs would not catch a slip-up of these two words. Spell-check is looking for words that aren’t in its dictionary, and words that resemble words in its dictionary but are possibly spelled wrong. Spell-check isn’t perfect. It doesn’t know and can’t guess what word you wanted or what word you meant, it can only judge the words on the page. If you used words that are all spelled correctly, it gives you a pass anyway.
Autocorrect suggests words that start with the same letters. It’s suggesting what word you may want to save time, but quite often, its suggestions are pretty off base. They don’t help you out, but they do make you laugh.
Emission is a noun, it’s related to the verb “emit.” Emissions are liquid or gas substances released by a body or machine into the air.
Omission is a noun, it’s related to the verb “omit.” It means something that was forgotten, misplaced, or left out.
The following story uses both words correctly:
It was the mid-1990s in middle America, and Emmett was shopping for cars. As he was flipping through information about different models, he noticed there was no indication about the carbon emissions ratings for each one. What a glaring omission, he thought.