Longman Dictionary of Contemporary English
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In employment law, constructive dismissal, also called constructive discharge or constructive termination, occurs when an employee resigns as a result of the employer creating a hostile work environment. Since the resignation was not truly voluntary, it is in effect a termination. For example, when an employer makes life extremely difficult for an employee, to attempt to have the employee resign, rather than outright firing the employee, the employer is trying to effect a constructive discharge.
The exact legal consequences differ between different countries, but generally a constructive dismissal leads to the employee's obligations ending and the employee acquiring the right to make claims against the employer.
The employee may resign over a single serious incident or over a pattern of incidents. Generally, the employee must have resigned soon after the incident.