9-Letter Words Containing OPER__

• a hard flap serving as a cover for (a) the gill slits in fishes or (b) the opening of the shell in certain gastropods when the body is retracted

• being in force or having or exerting force

• relating to or requiring or amenable to treatment by surgery especially as opposed to medicine

• a person secretly employed in espionage for a government

• someone who can be employed as a detective to collect information and assist in criminal investigations

• effective; producing a desired effect

• (of e.g. a machine) performing or capable of performing

• The art or trade of a cooper.

• The price paid to a cooper for work carried out.

• A cooper's workshop.

• A protein in human serum that complements part of the immune system

• United States industrialist who built the first American locomotive; founded Cooper Union in New York City to offer free courses in the arts and sciences (1791-1883)

• a craftsman who makes or repairs wooden barrels or tubs

• United States film actor noted for his portrayals of strong silent heroes (1901-1961)

• United States novelist noted for his stories of American Indians and the frontier life (1789-1851)

• make barrels and casks

• work together on a common enterprise or project