For all time, for all eternity; for an infinite amount of time.
- I shall love you forever.
For a very long time, 'an' eternity.
- We had to wait forever to get inside.
For an excessively long time.
- It took her forever to get dressed and ready for the party.
- The drive to his mothers' house took forever.
At all times, anytime, always.
- You'll have a home here forever, my son!.
Constantly or frequently.
- You are forever nagging me.
- Early in his boyhood he had learned to form ropes by twisting and tying long grasses together, and with these he was forever tripping Tublat or attempting to hang him from some overhanging branch.