noun
blithering idiot; bloody fool; total moron; dimwit
Strongly derogatory term for a person considered extremely foolish or incompetent. Often used in anger or as an insult.
このばかたれ！何をやっているんだ！
You blithering idiot! What are you doing?!
あんなばかたれに任せたら、仕事が
If you leave it to a total moron like that, the work will be a mess.
ばか is a more general and common term for 'fool' or 'idiot', while ばかたれ is a stronger, more emphatic insult.
あほ is a Kansai-dialect equivalent of ばか, often used playfully, whereas ばかたれ is harsher and not dialect-specific.
Compound of ばか (fool) and たれ (a pejorative suffix derived from the verb たれる, meaning 'to hang down' or 'to drip', used to intensify insults).