Section 2(b) in The Orissa Essential Services (Maintenance) Act, 1988
(b)"strike" means the cessation of work by a body of persons employed in any essential service acting in combination or a concerned refusal or a refusal under a common understanding of any number of persons who are or have been so employed, to work or to accept employment and includes-(i)unauthorised absence from duty in pursuance of a common understanding among the persons who unauthorisedly absent themselves from duty or under the direction of any other person or persons;(ii)refusal to work overtime where such work is necessary for the maintenance of any essential service;(iii)any other conduct which is likely to result in, or results in, cessation or substantial retardation of work in any essential service.
