1.
If you describe something as ~, you mean that it is very unpleasant. (INFORMAL, OLD-FASHIONED)
= horrible, horrid
ADJ
2.
If you describe someone as ~, you mean that they are behaving unkindly. (INFORMAL, OLD-FASHIONED)
= horrible, horrid
ADJ
BEASTLY
Meaning of BEASTLY in English
Collins COBUILD. Толковый словарь английского языка для изучающих язык Коллинз COBUILD (международная база данных языков Бирмингемского университета) . 2012