The word 'ard' literally means 'land'. Any place that humans can migrate to, colonize or live on, or any stellar system where life can exist is also 'ard'. All rocky planets in the universe also have 'land', just as on earth. This planet itself is too insignificant to be mentioned as a separate creation: there are billions on earth-like planets in the universe, and Quran 42:29 says that God has spread out living creatures throughout the universe (the 'skies and the land'). So 'land' is any place which sustains life: basically stellar systems made of matter, since we are all made out of star dust.
The word 'samaa' literally means 'sky': the space around us that we can seen from our land, and the plural 'samawaat' means 'skies'. Quran says that God created the 7 skies are created in 'layers' (67:3, 71:5). What we can observe is 'samaa ad-duniya': the 'sky of this world' or 'lowest sky', adorned with 'lamps' (stars) [67:3-5, 41:9-12]. Other skies (universes) are beyond the observable sky (universe) that we inhabit.
Then 65:12 would mean that other skies / universes also have land / matter, similar to ours. But each sky has its own physical law ['amr'] (41:12). God knows what it is like, and how they are different; we cannot know.