Common Lisp was a joint effort to make a good, portable, featureful Lisp specification. All the parties you mentioned were on the ANSI standard panel, hence "Common" and hence "Lisp".
Scheme was never a part of that effort and indeed it shouldn't have been, as it is a standalone language with its objectives and different semantics. It also at no point was ever called LISP, it was Scheme from the very first memo. It is extremely uncommon to Schemer to refer to his code as "I programmed it in Lisp", there is certainly its own, formed identity among the users.
LISP itself stems from original McCarthy implementation; its name bears the legacy of 7-bit teletypes of the day. But this point is well elaborated in the write-up we discuss.
Scheme was never a part of that effort and indeed it shouldn't have been, as it is a standalone language with its objectives and different semantics. It also at no point was ever called LISP, it was Scheme from the very first memo. It is extremely uncommon to Schemer to refer to his code as "I programmed it in Lisp", there is certainly its own, formed identity among the users.
LISP itself stems from original McCarthy implementation; its name bears the legacy of 7-bit teletypes of the day. But this point is well elaborated in the write-up we discuss.