i-adjective
formidable; not to be underestimated
Describes someone or something that should not be taken lightly; often used for opponents, challenges, or achievements.
彼は侮りがたい相手だ。
He is a formidable opponent.
そのチームの実力は侮りがたい。
The team's ability is not to be underestimated.
The base verb meaning 'to despise' or 'to make light of'; 侮りがたい is its negative potential form used as an adjective.
From the verb 侮る (anadoru, 'to despise') + がたい (gatai, 'difficult to'), literally 'difficult to despise'.