Jai guru deva om, (Sanskrit: जय गुरुदेव ॐ) is a mantra (a sacred word) that approximately defines as "glory to the shining remover of darkness".
"Jai" means "All hail/ Victory to".
"Guru" means "teacher/ educator".
"Deva" means "God/ Lord/ Demi-God".
"Om" is a sacred sound and a spiritual symbol of the Dharmic religion.
It can be paraphrased as "Victory to the Lord divine". It can also be a reference of a Maharishi's teacher as "All glory to Guru Dev".