Vocabulary

ਦੂਜੀ-ਤੀਜੀ
dooji-teeji

second or third (as in: there's no other option, no backup)

adjective
In this song
Midnight Call · Harkirat Sangha
Verse 3
You The One And Only ਨਾ ਕੋਈ ਦੂਜੀ-ਤੀਜੀ ਮੇਰੀ
You the one and only na koi dooji-teeji meri
You're the one and only, there's no second or third