- A1 a [eı] n plural A's a's1.) [U and C]the first letter of the English alphabet2.) [U and C]3.)the highest mark that a student can get in an examination or for a piece of work▪ I got an A in French.▪ Julia got straight As (=all A's) in high school.4.) an A studentAmE someone who regularly gets the best marks possible for their work in school or college5.) [U]used to refer in a short way to one of two different things or people. You can call the second one B▪ A demands £500, B offers £100.→plan A at ↑plan1 (5)6.) from A to Bfrom one place to anotherget/go from A to B▪ Hiring a car was the best way to get from A to B.7.) from A to Zdescribing, including, or knowing everything about a subject▪ the history of 20th century art from A to Z8.) A34, A40 etc→↑A-road9.) [U]a common type of blood→↑A levelA 2A2the written abbreviation of amp or amps
Dictionary of contemporary English. 2013.