I disagree.
Firstly, there's a difference between "public cloud" and "private cloud," where 'public' implies "someone else's computer," but given this, and given that you can do private clouds, clearly the ownership of the hardware is not the defining characteristic for "cloud."
Rather, I'd argue the definition for "cloud" has to include -- perhaps more importantly than any other part of the definition -- the ability to request a resource from the system via an API and get it automatically (barring resource constraint issues or artificial limits) without human involvement. THAT is what makes it "cloud," irrespective of whether you're making that API call against the systems your own IT folks set up to get a resource within your datacenter or you're making that call against AWS.
Don't make me laugh.
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