fast generation of random string not in a dictionary

FYI: This will be integrated into a node.js project that also uses mongoDB I need some JS code that quickly(sub-500ms) generates a random 6 char string that matches crockford's base32 BUT can NOT contain any dictionary words >>> these "words" should be classified as reserved for manual allocation later <<< When searching for potential reserves words explore substitution possibilities: 1 = 1 I i L l and 0 = 0 O o Also the dictionary search will need to cover languages that overlaps with ascii. German, French, English, Spanish... etc more! i.e. *a 2 letter word can occur a maximum ONE time in a sequence before it is considered reserved! Reserved: "2HAPPY", "HAHAHA", "CATD0G", "11ke1t", "ANDD1E", "YEARRK" Not Reserved: "AYRP6V", HAADHA","J52RSY", AN001E""YE5RRK" I would be open to a high-performance algorithm or a rainbow table containing all 1073741823 combinations indicating what sequences are reserved and not.