In Lucretious poem De Natura, he has
They [atoms] move through the void
In contemporary usage a vacuum is the the removal of all matter from space, it stems from Latin adjective vacuus for empty or void. What I am curious about is what was then (in Antiquity) understood by the void.
My understanding is that the greek atomists were forced to their theory by critiquing Parmenides monism where he denied the existence of the void (that is, is not) in his poem Of Nature:
the one, that is and that is not not to be,
but the other, that is not and that must not be,
this, I tell you, is a path wholly without report:
for neither could you apprehend what is not, for it is not to be accomplished,
nor could you indicate it.
but nothing it is not
It certainly seems that the Ash'arite atomists in Islamic Philosophy (the Falsafa) seemed to go that step further: understanding that space is something they atomised it too.
Certainly in contemporary physics there is no void. Space itself is something. Similarly in contemporary mathematics, for example: zero or nothing was first understood prosaically and negatively as the lack of something, and is now understood positively as a process (that is functionally), as the identity of the system within which these numbers inhabit. Another example: a manifold was first thought of inside euclidean space, this is the extrinsic view; now via a cut by Occams Razor a more parsimonius view, the more elegant view, is to remove the extrinsic euclidean space, this stage within which the manifold is placed and enacted and view it intrinsically, that is solely for-itself and in-itself.
Is there any evidence that any followers of Parmenides asserted this, that is Space is a something? Certainly it seems the obvious thing to assert if we take Parmenides seriously.