In this Part, save where the context otherwise requires -

"employer" means a person for whom one or more workers work or have worked or normally work or seek to work having previously worked for that person;

"trade dispute" means any dispute between employers and workers which is connected with the employment or non-employment, or the terms or conditions of or affecting the employment, of any person;

"trade union" means a trade union which is the holder of a negotiation licence under Part II of the Trade Union Act, 1941;

"worker" means any person who is or was employed whether or not in the employment of the employer with whom a trade dispute arises, but does not include a member of the Defence Forces or of the Garda Síochána;

"industrial action" means any action which affects, or is likely to affect, the terms or conditions, whether express or implied, of a contract and which is taken by any number or body of workers acting in combination or under a common understanding as a means of compelling their employer, or to aid other workers in compelling their employer, to accept or not to accept terms or conditions of or affecting employment;