Mum \Mum\, a. [Of imitative origin. Cf. Mumble.]

Silent; not speaking. --Thackeray.

The citizens are mum, and speak not a word. --Shak.

Source: Webster's Revised Unabridged Dictionary (1913)
 

Mum \Mum\, interj. Be silent! Hush!

Mum, then, and no more. --Shak.

Source: Webster's Revised Unabridged Dictionary (1913)
 

Mum \Mum\, n. Silence. [R.]

--Hudibras.

Source: Webster's Revised Unabridged Dictionary (1913)
 

Mum \Mum\, n. [G. mummere, fr. Christian Mumme, who first brewed it in 1492.]

A sort of strong beer, originally made in Brunswick, Germany. --Addison.

The clamorous crowd is hushed with mugs of mum. --Pope.

Source: Webster's Revised Unabridged Dictionary (1913)