The phrase “abnormally large amount” can be replaced by several synonyms that add variety and nuance to your language.
One synonym is “excessive quantity”. This term emphasizes that there is more than what is considered normal or reasonable. For example, “There was an excessive quantity of food at the party.” It implies that the amount is beyond what is typically expected.
“unusually large number” is another option. This focuses on the number rather than the amount, but still conveys the idea of something being much larger than normal. For instance, “There were an unusually large number of people at the concert.”
“enormous quantity” is a more forceful synonym. It suggests a truly massive amount. For example, “The factory produced an enormous quantity of goods.” This term makes it clear that the amount is extremely large.
“outsize amount” also works. “Outsize” implies being larger than the usual or expected size. For example, “The project required an outsize amount of resources.” It gives the sense that the amount is disproportionately large.
“exorbitant amount” is a more formal synonym. It often implies that the amount is excessive and perhaps even unreasonable. For example, “The price of the luxury car was an exorbitant amount.”