original title
Refers to the title of a work (book, film, song, etc.) in its original language or as first published, before translation or adaptation.
The original title of this movie is in French.
The original title of this movie is 'Frozen'.
I changed the original title of the paper.
The novel was published under its original title.
タイトル is a casual, everyday loanword for a title, while 原題 is used specifically to mean the original-language title.
原題 is a work's title in its original language, while 邦題 is the Japanese title given to it for release.
Compound of 原 (original) and 題 (title).