Adi refers to ornaments, jewels, or fine adornments — the decorative items that signify beauty, status, and honor. It appears about 13 times and is notably used both for bridal adornment (the beloved decking herself with jewels) and for God's lavishing of covenant beauty upon Israel.
In Ezekiel 16, God describes Jerusalem as a bride whom He adorned with every kind of adi — gold, silver, and precious stones — to illustrate covenant blessing. The tragedy is that Israel used this beauty for harlotry. Jeremiah 2:32 asks whether a bride would forget her adi — making God's being forgotten by His people even more shocking. In Isaiah 61:10, the messianic figure adorns himself like a bridegroom with his adi, connecting adornment with eschatological joy and bridal imagery that runs through the entire Bible into Revelation 21.