Tuesday \Tues"day\ (t[=u]z"d[asl]; 48), n. [OE. Tewesday, AS. Tiwes d[ae]g the day of Tiw the god of war; akin to OHG. Zio, Icel. T[=y]r, L. Jupiter, Gr. Zey`s;, cf. OHG. Ziostac Tuesday, G. Dienstag, Icel. T[=y]sdagr. [root]244. See Deity, Day, and cf. Jovial.]

The third day of the week, following Monday and preceding Wednesday.

Source: Webster's Revised Unabridged Dictionary (1913)