noun
A decorative object, often used for seasonal displays like Christmas trees, or as a general term for an embellishment.
クリスマスツリーにオーナメントを飾った。
I decorated the Christmas tree with ornaments.
このオーナメントは手作りです。
This ornament is handmade.
飾り is a broader native Japanese word for decoration or adornment, while オーナメント specifically refers to a decorative object, often with a Western or seasonal connotation.
Loanword from English 'ornament'.