in ‧ sub ‧ or ‧ di ‧ na·tion /ˌɪnsəbɔːdəˈneɪʃ ə n, ˌɪnsəbɔːdɪˈneɪʃ ə n $ -ˌbɔːrdnˈeɪ-/ BrE AmE noun [uncountable] formal
when someone refuses to obey a person who has more authority than them SYN disobedience :
Howell was fired for gross insubordination.
—insubordinate /ˌɪnsəˈbɔːdənət, ˌɪnsəˈbɔːdɪnət $ -ɔːr-/ adjective