This is the 554th most frequent Greek word.
άλλος
"Άλλος" means "other" or "another" in English.
Here, 'άλλος' ('another') is used to indicate desire for a different instance of something, in this case 'coffee'.
Θέλω έναν άλλο καφέ.
I want another coffee.
In this sentence, 'άλλος' ('other') refers to a different or additional individual among a group, specifically 'the other student'.
Ο άλλος μαθητής πήγε πρώτος.
The other student went first.
Here, 'άλλες' ('other') conveys variability within a set of occurrences, distinguishing between walking and running incidents.