What does alder or aller mean?
The definition of alder and aller
Al”der, Al”ler, a.
Etym: [From ealra, alra, gen. pl. of AS. eal. The d is excrescent.]

Of all; — used in composition; as, alderbest, best of all, alderwisest, wisest of all. [Obs.] Chaucer.