- Someday means “at an indefinite time in the future.”
- Some day refers to one day that is perhaps unknown or unspecified.
Someday and some day are easy expressions to confuse because they differ by just one space. Learn how to keep them straight in this article.
What Does Someday Mean?
Someday is an adverb. It refers to future events that will occur at an indefinite time. Here are two examples of someday in a sentence:
What Does Some Day Mean?
Now, let’s look at some day with a space between the two words. We have an adjective (some) and a noun (day). Some means “unspecified” in this context. When it describes day, it means a single day that is unknown or unspecified. Let’s clarify with two examples of “some day” in a sentence.
from Grammarly Blog https://www.grammarly.com/blog/someday-vs-some-day/