In sections 137 to 143—
"advertisement" includes every form of advertisement or notice, whether to the public or not, and references to publishing an advertisement shall be construed accordingly;
"employment" means employment under a contract of employment, and related expressions shall be construed accordingly; and
"employment agency" means a person who, for profit or not, provides services for the purpose of finding employment for workers or supplying employers with workers, but subject to subsection (2) below.
For the purposes of sections 137 to 143 as they apply to employment agencies—
References in sections 137 to 143 to being or not being a member of a trade union are to being or not being a member of any trade union, of a particular trade union or of one of a number of particular trade unions.
The remedy of a person for conduct which is unlawful by virtue of section 137 or 138 is by way of a complaint to an employment tribunal in accordance with this Part, and not otherwise.