Satguru - This Punjabi word means "true guru" or true spiritual guide or teacher. (Gurmukhi ਸਤਿਗੁਰ sat means true; Guru means en-lightener); literally: true teacher.

The word is also usually used to refer to God as the ultimate teacher is God, but can be interchanged with Guru (spiritual guide). The word appears more than 2500 times in the Guru Granth Sahib. It implies that the students have faith that the guru can be trusted and will lead them to moksha or enlightenment or inner peace.

SGGS Page 10 Full Shabad
ਜੋ ਸਤਿਗੁਰ ਸਰਣਿ ਸੰਗਤਿ ਨਹੀ ਆਏ ਧ੍ਰਿਗੁ ਜੀਵੇ ਧ੍ਰਿਗੁ ਜੀਵਾਸਿ ॥੩॥

Jo saṯgur saraṇ sangaṯ nahī ā­ė ḏẖarig jīvė ḏẖarig jīvās. ॥3॥
Those who have not sought the Sanctuary of the True Guru and the Sangat,
the Holy Congregation; cursed are their lives, and cursed are their hopes of life. ॥3॥

Other others from Guru GranthEdit

On Page 468, it is written: ਸਤਿਗੁਰੁ ਭੇਟੇ ਸੋ ਸੁਖੁ ਪਾਏ ॥ Saṯgur bẖete so sukẖ pā▫e. which means "One who meets the True Guru finds peace."

Sat + Guru = Who have Knowledge of Truth, Who tells, What is real Dharam, What are you doing and for what you are here for. Satguru = Person, Satguru = Chitt and Satguru = Parameshwar. But to get eternal peace you have to agree and follow with his wordings (ਹਰਿ ਕਾ ਨਾਮੁ ਮੰਨਿ ਵਸਾਏ ॥)