Zeste vs Zest

Zeste refers to a citrus fruit peel (used in cooking). It can also be used ironically to mean a hint or touch of something: un zest de folie - a hint of madness.
Zest can mean zeste, but more commonly indicates great enthusiasm - un entrain, un désir, un goût. Zest for life - un goût de vivre.

Zone vs Zone

Zone usually means a zone or an area. It can also refer to a slum.
Zone = zone.