Rickettsiales rickettsial • rickettsialpox · · · Info · Definitions · Characters · · Rickettsiales · · Text Latin · · Script 13 · · Length Definitions · · · (noun) pleomorphic Gram-negative microorganisms. Synonyms: order Rickettsiales. · · Noun Definition 1 Characters · · R latin capital letter r U+0052 a latin small letter a U+0061 c latin small letter c U+0063 e latin small letter e U+0065 i latin small letter i U+0069 k latin small letter k U+006B l latin small letter l U+006C s latin small letter s U+0073 t latin small letter t U+0074