Small?

I agree, less than 5 would be on the small side. That's a very nice average din
On this site five would be small. Based on what guys say is their penis length it is small. But...

When doctors and nurses measured in a study the average was 5.1 inches in one study and 5.3 inches in another study.

There are micro penises out there less than three inches erect. Not many, but they pull the average down.
 
On this site five would be small. Based on what guys say is their penis length it is small. But...

When doctors and nurses measured in a study the average was 5.1 inches in one study and 5.3 inches in another study.

There are micro penises out there less than three inches erect. Not many, but they pull the average down.

I agree. Less than 5 is not exactly small. It's below average, but I would say officially "small" would be 3" or less. Much like "big" is generally 7" or longer.