IPA: /ˈnær.oʊ.ɪst/
KK: /ˈnɛrəʊəst/
The smallest width or least distance between two sides or edges.
This is the narrowest path in the forest, making it difficult for two people to walk side by side.
Comparative: narrower
Superlative: narrowest
Narrowest → It is formed from "narrow" (from Old English "nearwe", meaning tight or constricted) and the superlative suffix "-est" (meaning most). The word "narrowest" means the most tight or constricted in width or extent.
Think of something that is the "most tight" or "most constricted" — that's what narrowest means.