Wiktionary
n. The sequence of a collection of items (such as words in a dictionary) arranged in order by position in the alphabet.
Wikipedia
Alphabetical order is a system whereby strings of characters are placed in order based on the position of the characters in the conventional ordering of an alphabet. It is one of the methods of collation.
To determine which of two strings comes first in alphabetical order, their first letters are compared. If they differ, then the string whose first letter comes earlier in the alphabet is the one which comes first in alphabetical order. If the first letters are the same, then the second letters are compared, and so on. If a position is reached where one string has no more letters to compare while the other does, then the first (shorter) string is deemed to come first in alphabetical order.
Capital letters (upper case) are generally considered to be identical to their corresponding lower case letters for the purposes of alphabetical ordering, though conventions may be adopted to handle situations where two strings differ only in capitalization. Various conventions also exist for the handling of strings containing spaces, modified letters (such as those with diacritics), and non-letter characters such as marks of punctuation.
The result of placing a set of words or strings in alphabetical order is that all the strings beginning with the same letter are grouped together; and within that grouping all words beginning with the same two-letter sequence are grouped together; and so on. The system thus tends to maximize the number of common initial letters between adjacent words.
Usage examples of "alphabetical order".
As small groups of students were called forwards in alphabetical order, those left behind muttered incantations and practised wand movements, occasionally poking each other in the back or eye by mistake.
With so short and difficult a text, however, the time is not only understandable, but admirable/ Moreover, the dancers caper in no recognizable pattern when placed in alphabetical order, and when they pose in a graduated order of choreography, no regularity appears in the letters.
Once, when I was scared to fail in an examination, I reorganized all the attic and later I placed by alphabetical order discs of my brother and prescriptions of kitchen of my mother.
It is for the same kind of reason that the words in dictionaries are arranged in alphabetical order.
Marriages were indexed in alphabetical order and bound in volumes.