Agency Worker - (noun)
An agency worker is someone who gets a job through an employment agency. The work is often called 'temporary work', 'temping' or 'agency work'. The firm who hires the agency worker pays the employment agency, and the employment agency then pays the worker.
Source: Adapted from www.nidirect.gov.uk
Example of Use: Agency workers often have poorer pay and conditions than permanent workers employed directly by the employer.