(theology) From the work worked; referring to sacraments deriving their power from Christ's work rather than the role of humans, and thus not requiring faith to be effective.

(rail transport) The operation of a train without a conductor or guard as a cost-cutting measure; one-man operation.

(euphemistic) A military situation resembling a war (usually referencing the events of February 2022 in the Russo-Ukrainian War)

(historical) A Canadian democratic socialist political party active between 1932 and 1961 which served as the predecessor of the New Democratic Party.

(obsolete) effective; practical; operative [16th–17th c.] / Of or relating to operations.

(obsolete) A laboratory. [16th–17th c.] / (medicine) A room in which a dentist (or assistant) performs tasks on the patient. [from 20th c.]

plural of operatory

(mathematics) Of or pertaining to an operator

The office of an operator / The right to operate an oil well

plural of operatorship