Cubit
/ˈkjuːbɪt/
Definition 1 of 1
Pro Tip 1/3Historical Measure
A cubit is not used in modern measurements; it's historical and mostly found in ancient texts. 
The dimensions of the ancient structures were often recorded in cubits.
Pro Tip 2/3Varied Length
The exact length of a cubit could vary because it was based on the measurer's arm. 
In ancient Egypt, a cubit was different than a Hebrew cubit.
Pro Tip 3/3Biblical Reference
Cubit is often mentioned in the Bible, so it's useful to know for religious or historical studies. 
Goliath was said to be six cubits and a span tall.