The phrase seeing as or seeing that is used to introduce a reason or explanation for what is being said. It functions as a conjunction in English.
When someone says “seeing as” or “seeing that,” they mean “because” or “since.” It highlights a cause before explaining a conclusion.
Example: Seeing as it's raining, we should probably stay indoors.
This expression appears naturally in informal and conversational English while being accepted in written communication as well.
Author’s Summary: The phrase seeing as/that expresses a causal link meaning “because” or “since,” frequently used in spoken English to justify or explain a statement.