IPA: /ˈɪn.səl.bɜːrg/
KK: /ˈɪn.səl.bɜːrg/
A hill or mountain that rises sharply from the surrounding area, often standing alone and not part of a larger range.
The hiker was excited to reach the top of the inselberg, where the view was breathtaking.
Inselberg is a compound word formed from "Insel" (from German, meaning island) and "Berg" (from German, meaning mountain). The term describes a mountain or hill that rises abruptly from a plain or plateau, resembling an island in a sea of flat land.
Think of an 'island' ('Insel') rising like a 'mountain' ('Berg') from flat land — that's what an inselberg is.
No commonly confused words.