1. A small decorative object of special beauty, rarity, or curiosity.
2. A miniature book, especially one that is finely crafted; a thumb book.
Etymology: Old French beubelet, trinket or jewel, from belbel, plaything (a reduplication of bel, pretty).
The more common 'bauble' is a similar word with similar origins, and it predates 'bibelot' by a few centuries.
It appears that the first use of bibelot was in the early 1800s, while bauble was in use in the 1300s.
'Bauble' generally refers to something of little value, while bibelot might not.
The Bibelot was the name of a literary anthology published by Thomas Bird Mosher between 1895 and 1914.
This thumb book was published in 1753, so it wouldn't have been called a bibelot until later.