Introduction:- Industrial dispute is the dispute affecting large groups of workmen and employers ranged on opposite sides on some general questions on which each group is bound together by a community of interests — such as wages, bonuses, allowances, pensions, provident fund, number of working hours per week, holidays and so on, D.N. Banerji v. P.R. Mukherjee, AIR 1953 SC 58, 61: 1953 SCR 302.

Strike:-

Refusal to work under concert constitutes strike, Model Mills Nagpur Ltd. v. Dharam Das, AIR 1958 SC 311.  A concerted discontinuance by labourers of work for a particular employer or body of employers, either after termination of stipulated notices to determine their engagements or without the giving of any such notices; a lock-out being a converse discontinuance by employers of employment.  ‘Strike’ means the cessation of work by a body of persons employed in any essential service acting in combination or a concerted refusal or a refusal under a common understanding of any number of persons who are or who have been so employed to continue to work or to accept employment and includes —

(i) refusal to work overtime where such work is necessary for the maintenance of any essential service;

(ii) any other conduct which is likely to result in or results in, cessation or substantial retardation of work in any essential service, [Section 2(c), Essential Services Maintenance (Assam) Act, 1980.

Lockout:-

Lockout means  the closing of a place of employment, or the suspension of work, or the refusal by an employer to continue to employ any number of persons employed by him, Kairbetta Estate v. Rajamanickam, AIR 1960 SC 893: (1960) 3 SCR 371: (1960) 2 LLJ 275, Para 7.