We'd like to introduce you to some close cousins of "desire." All trace their roots to the Latin sider-, meaning "heavenly body." Desiderare, meaning "to long for," was born when Latin de- was prefixed to "sider-." "Desiderare" begat Anglo-French desirer, which in turn brought forth English "desire," "desirous," and "desirable" in the 13th and 14th centuries. But many years later, in the 17th century, English acquired "desideration" ("longing"), "desiderate" ("to wish for"), and finally "desideratum," all of which can lay claim to direct ancestry from "desiderare."