Dismissal or firing is generally thought to be the fault of the employee, whereas a layoff is generally done for business reasons (for instance a business slowdown or an economic downturn) outside the employee's performance.
Australian Unions. In Australia, a union is sometimes referred to as a trade union or a labour union. A union is an organisation of workers or employees who have joined together to achieve common goals. These goals can include seeking higher pay and better working conditions, fighting for job security and protecting the integrity of a trade.
Legal Definition of labor union. : a labor organization usually consisting of workers of the same trade that is formed for the purpose of advancing its members' interests (as through collective bargaining) in respect to wages, benefits, and working conditions â see also craft union, bargaining unit.