C programming, write a program that arrange them into alphabetical order by using struct form.

And can you teach me what the number in [ ] means ?

Here is the things to arrange into alphabetical order

const struct entry dictionary[500] = { {"zincic", "Pertaining to, containing, or resembling, zinc; zincous."}, {"zonulet", "A zonule."}, {"zymophyte", "A bacteroid ferment."}, {"zygenid", "Any one of numerous species of moths of the family Zygaenidae, most of which are bright colored. The wood nymph and the vine forester are examples. Also used adjectively."}, {"zumological", "Alt. of Zumometer"}, {"z", "Z, the twenty-sixth and last letter of the English alphabet"}, {"zoophorous", "The part between the architrave and cornice; the frieze; -- so called from the figures of animals carved upon it."}, {"zoisite", "A grayish or whitish mineral occurring in orthorhombic, prismatic crystals, also in columnar masses. It is a silicate of alumina and lime, and is allied to epidote."}, {"zincide", "A binary compound of zinc."}, {"zenith", "That point in:%s/^ the visible celestial hemisphere which is vertical to the spectator; the point of the heavens directly overhead; -- opposed to nadir."}, {"zygapophysis", "One of the articular processes of a vertebra, of which there are usually four, two anterior and two posterior. See under Vertebra."}, {"zoomorphic", "Of or pertaining to zoomorphism."}, {"zamite", "A fossil cycad of the genus Zamia."}, {"zodiacal", "Of or pertaining to the zodiac; situated within the zodiac; as, the zodiacal planets."}, {"zittern", "See Cittern."},

};