a wet blanket

Webster's Dictionary (GCIDE)

Blanket \Blan"ket\, n. [F. blanchet, OF. also blanket, a woolen waistcoat or shirt, the blanket of a printing press; prop. white woolen stuff, dim. of blanc white; blanquette a kind of white pear, fr. blanc white. See Blank, a.]

1.A heavy, loosely woven fabric, usually of wool, and having a nap, used in bed clothing; also, a similar fabric used as a robe; or any fabric used as a cover for a horse. [1913 Webster]

2.(Print.) A piece of rubber, felt, or woolen cloth, used in the tympan to make it soft and elastic. [1913 Webster]

3.A streak or layer of blubber in whales. [1913 Webster]

Note: The use of blankets formerly as curtains in theaters explains the following figure of Shakespeare. --Nares. [1913 Webster]

Nor heaven peep through the blanket of the dark To cry, "Hold, hold!"— Shak.[1913 Webster]

Blanket sheet, a newspaper of folio size.

A wet blanket, anything which damps, chills, dispirits, or discour?ges. [1913 Webster]