Astaghfirullah
literally translates to "I seek forgiveness in Allah". In a religious way,
people can recite it during meditation or say it to others to show humility- to say that Allah is greater or that goodness comes from Allah. In popular culture,
people can say this if they see something wrong or shameful (context applies).
Example 1:
Person- Hatija, your lecture was truly insightful!
Hatija- Astaghfirullah,
Allah gives us the
knowledge.
Example
2:
A group of religious people watching a movie together when a sex scene comes on
-"Astaghfirullah" in congregation.