What does "bookplate" mean?

A printed piece of paper pasted on one of the pages of a book, most often on the inside front cover, showing ownership and thus deterring theft.

Bookplate

Common synonyms include: ex libris, book label, bookplate art, bookplate design, bookplate related, brand.

noun, verb

noun, verb ·Uncommon ·Advanced level

Noun

1
A printed piece of paper pasted on one of the pages of a book, most often on the inside front cover, showing ownership and thus deterring theft.
"By the bed there was a bookcase with old French novels, left-behind Frederick Forsyths, odd leather-bound volumes of history and memoirs with the coroneted Kessler bookplate."
2
a label identifying the owner of a book in which it is pasted wordnet

Verb

"This is my book. Do you see the bookplate here?"

From book + plate.