You might be referring to "imminent" "eminent" "immanent".
"Imminent" is a commonly used adjective to describe something which is going to happen very soon but we don't know the exact time e.g. an increase in the oil price is imminent
"Eminent" - is a formal but well-known and used adjective to describe someone who is very senior, well-respected and experienced in their field of work or study
e.g. He is an eminent physician
"Immanent" is a very unusual word used in philosophy. It's opposite is transcendent. It is used to explain that the origin of a "being" and / or its existence comes from within i.e. it was not created or held in being by an external, transcendent being. I may not have expressed this perfectly as I am only an armchair philosopher, not an eminent specialist!