Meaning of -ACEOUS in English
a suffix with the meanings "resembling, having the nature of," "made of," occurring in loanwords from Latin ( cretaceous; herbaceous ) and forming adjectives in English on the Latin model ( ceraceous ), esp. adjectival correspondents to taxonomic names ending in -acea and -aceae: rosaceous.
[ -aceus; see -OUS ]
Random House Webster's Unabridged English dictionary. Полный английский словарь Вебстер - Random House . 2012