In this Part -

"cease" means cease either temporarily or permanently and from whatever cause;

"lock-out" 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 in consequence of a dispute, done with a view to compelling those persons, or to aid another employer in compelling persons employed by him, to accept terms or conditions of or affecting employment;

"notice of intention to claim" has the meaning assigned to it by section 12;

"redundancy certificate" has the meaning assigned to it by section 18;

"strike" means the cessation of work by a body of persons employed acting in combination, or a concerted refusal or a refusal under a common understanding of any number of persons employed to continue to work for an employer in consequence of a dispute, done as a means of compelling their employer or any person or body of persons employed, or to aid other employees in compelling their employer or any person or body of persons employed, to accept or not to accept terms or conditions of or affecting employment.