Cruel and unfair in the way it uses power. A tyrannous ruler, government, or law controls people harshly, does not listen, and cannot be argued with. It is a formal, literary word — you meet it in books, poems, history writing, and speeches, almost never in everyday talk. In normal English people say 'tyrannical', and 'tyrannous' feels older and more written; the two mean the same thing, though 'tyrannous' carries a stronger smell of poetry (Shakespeare uses it). Writers also stretch it past real rulers, to anything that holds you down and gives you no choice — a tyrannous heat, a tyrannous silence, a tyrannous father. That stretched use is common in literature, so if you meet the word outside politics, look for the feeling of 'this thing rules me and I cannot escape it'.

暴虐的、專橫的（書面語，比 tyrannical 更文言）