Meaning

noun a strip of land projecting into a body of water

noun a sleeveless garment like a cloak but shorter

originFrom French cape, from Old Occitan capa, from Late Latin cappa (“cape”). The second sense ("superhero") is metonymic from the fact that many superheroes wear capes. Likewise, the verb sense "defend, praise" alludes to the stereotypical depiction of superheroes wearing capes when they come to people's defense. (Compare caped crusader.) Doublet of capa and cappa.

Etymology from Wiktionary, CC BY-SA 3.0