longlasting

As adjectives the difference between permanent and longlasting

is that permanent is without end, eternal while longlasting is lasting a long time.

As a noun permanent

is a chemical hair treatment imparting or removing curliness, whose effects typically last for a period of weeks; a perm.

As a verb permanent

is to perm (the hair).

As adjectives the difference between neverending and longlasting

is that neverending is having no end or being endless while longlasting is lasting a long time.