(informal) To an extraordinary degree.

Something additional, such as an item above and beyond the ordinary school curriculum, or added to the usual charge on a bill.

Beyond what is due, usual, expected, or necessary; extraneous; additional; supernumerary. / (dated) Extraordinarily good; superior.

Denotes more.

Outside of, beyond.

plural of extra extra extra large

(uncountable) One of several sizes to which an item may be manufactured. / (countable) An item labelled or denoted as being that size. / (countable) One who fits an item of that size.

(uncountable) One of several sizes to which an item may be manufactured. / (countable) An item labelled or denoted as being that size. / (countable) One who fits an item of that size.

plural of extra extra extra small

(especially clothing) That is extra extra extra small (the manufactured size). / Used other than figuratively or idiomatically: see extra, small.