What is 5 eggs in a recipe called?

5 eggs is 5 eggs.

Eggs come in different sizes, in a recipe the average egg expected to be used is large eggs. One dozen large eggs weigh 24 - 27 ounces with 24 ounces being the norm.

5 large eggs weigh 10 to 10 1/2 ounces

for egg size substitutions:
petite eggs weigh 15 ounces per dozen (8 = 5 lg. eggs)
small eggs weigh 18 ounces per dozen (7 = ~5 lg. eggs)
medium eggs weigh 21 ounces per dozen (6 = ~5 lg. eggs)
large eggs weigh 24 ounces per dozen
extra large eggs weigh 27 ounces per dozen (4 1/2 = ~5 lg. eggs)
jumbo eggs weigh 30 ounces per dozen (4 = 5 lg. eggs)

**and extra jumbo or double eggs are typically over 33 ounces per dozen (these are often classed grade B eggs and not sold retail, unless part of a liquid or dried egg product. But you can get them from a farm)