This page provides all possible meanings and translations of the word half title
half title, bastard title(noun)
a first page of some books displaying only the title of the book
The half title, or bastard title, is a page carrying nothing but the title of a book— as opposed to the title page, which also lists subtitle, author, publisher and similar data.
The half title can have some ornamentation of the book's title, or it can be plain text.
Theodore Low De Vinne distinguishes between half title and bastard title in his series The Practice of Typography, saying:
Find a translation for the half title definition in other languages: