It is a graphic novel, it's just not an original graphic novel (OGN). Trades are graphic novels. I know it's a pet peeve that some don't say comics and just say graphic novels, but we can still say graphic novels.
We wouldn't be able to call Watchmen a graphic novel either then, if collected things aren't... hah yeah I don't even remember what we're talking about.
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One Piece: Pirates with style!
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