A protruding portion...

[FlamedToACrisp]

...is a peninsula, not a peninsular!

Peninsular means 'of or like a peninsula.' The Peninsular Wars were so called because they took place on a peninsula.

Thanks for listening.

Mmmmmmmmm very good.

It is from the Latin ‘Paene’ meaning almost, and ‘Insula’ meaning island , because it is just that, almost an island.

I do admire a Latin derivation.