The word "extra" means something that is additional or more than what is normal or expected. It can also refer to someone who is overacting or exaggerating. Full definition
A lack of carbs in food can possibly be made up for in extra amounts of protein. (dogfood.co)
With extra time for planning provided by their administration, the teachers explore a variety of resources for viable enrichment activities and find many options among materials prepared for students considered gifted and talented. (ascd.org)
If each of the two arms of the legislature is a carbon copy of the other then all you are doing is adding extra cost for no additional benefit. (nextleft.org)