Meaning of -A in English
a plural ending of nouns borrowed from Greek and Latin: phenomena; criteria; data; errata; genera.
a feminine singular ending of nouns borrowed from Latin and Greek, also used in Neo-Latin coinages to Latinize bases of any origin, and as a Latin substitute for the feminine ending - e of Greek words: anabaena; cinchona; pachysandra.
an ending of personal names forming feminines from masculines: Georgia; Roberta.
[ -a (see -A 2 ), as Claudia, fem. of Claudius ]
a suffix designating the oxide of the chemical element denoted by the stem: alumina; ceria; thoria.
[ prob. generalized from the -a of MAGNESIA ]
Random House Webster's Unabridged English dictionary. Полный английский словарь Вебстер - Random House . 2012