/ˌənəˈfɪʃəl ˈstraɪk/ – Phrase
Definition: cuộc đình công không chính thức, cuộc đình công không được công đoàn chấp thuận.
A more thorough explanation: An unofficial strike refers to a work stoppage or strike action undertaken by employees without the formal approval or authorization of their trade union or employer. This type of strike is not officially recognized or sanctioned by the relevant labor union or employment contract.
Example: The employees engaged in an unofficial strike, which was not authorized by the union or in accordance with the collective bargaining agreement.