|Origin:||Probably from extraordinary|
ex‧tra1 S1 W2
1 [only before noun]
more of something, in addition to the usual or standard amount or number:
Could you get an extra loaf of bread?
Allow extra time for your journey.
Drivers are advised to take extra care.
Residents can use the gym at no extra cost.
an extra ten minutes/three metres etc
I asked for an extra two weeks to finish the work.
2 [not before noun]
if something is extra, it is not included in the price of something and you have to pay more for it:
Dinner costs $15 but wine is extra.