1
general::
1. Such a large number, as in There were so many guests that we didn't have enough chairs. [First half of 1200s] 2. An unspecified number, as in There allegedly are so many shrimp per pound, but of course the exact number depends on their size and weight. [First half of 1500s] 3. Forming a group, as in The reporters turned on the speaker like so many tigers let loose. [c. 1600]
American Heritage Idioms