alias (adv.) Look up alias at Dictionary.com
mid-15c., "otherwise called," from Latin alias (adv.) "at another time," in Late Latin also "in another way, under other circumstances," from alius "another, other, different," from PIE *al- (1) "beyond" (source also of Sanskrit anya "other, different," Avestan anya-, Armenian ail, Greek allos "another," Gothic aljis "other," Old English elles "otherwise, else," Modern English else).
alias (n.) Look up alias at Dictionary.com
"assumed name," c. 1600, from alias (adv.).