A verse from a song of praise about the Planai which can be found in the yearbook of Austrian and German alpine society from the year 1916, starts with these lines. And with this, the problem of an apparent double meaning rears its head.
If one wants to be more familiar with the meaning of the name Planai, one should attempt to find out about the secret history of its change in meaning over the years.
It would be going a little too far if we were to quote all of the comparisons in language development of the Alps. It is sufficient to note how the Romanised tribes, the Germanics and even the Slavic settlers were eventually assimilated by the invading Bavarians.
Different conceptions of language development and different colourful dialects provide scope for differences of opinion. Name researchers tend towards the belief that because mountains lacked meaning in early years, mountain names are in fact young and in many cases they come from a quite simple source or origin and therefore there is no need to try and interpret them by focusing on the origins of language.

We will now look at the different ways in which Schladming’s local mountains have been written by looking at how they appear in old maps and plans and in the original land register, e.g Schladminger Käubling, Schladminger Kalbling, Schladminger Kaibling, Planai, Planei, Planay.
While the word “Kaibling” is simply written differently due to dialect, the prefix of Planai has remained unchanged. We come across the name “Kaibling” for peaks three times in the Enns valley alone, and the derivatives of “kahl” or “Kahler” do not really make a difference to the meaning. The limited morphology of the name of this peak through the different forest boundaries provides useful evidence. With the name Planai, we have to dig a little deeper. However this name is fairly common throughout the Alps. It appears in such derivatives as “planus”, or “planities” and means “flat/level surface”. Place names like Plan, Planer, Planner, Plon, Ploner, Planetzen or even the name Planei are common for small villages found south of the Reschen pass.
So with our Planai, it is more than likely the name has nothing to do with the Schladming Kaibling peak, but rather has more of a link to the flat pastures found in the East, so more of a farmland name! But from this there is something else to consider: During the last ice age, glacial moraines were covered the Enns valley, and these can be seen quite strikingly today.  On the Planai we can see them in the areas of Bruckmoos and quite easily in the upper part of Quellbodens (Worldcup start 1973). These moraines on the North face of the Schladming Kaibling were registered in the Land Registry in the past few centuries.
The Schladming pastures of the Fastenberger farmers create a flat area which is called a “Planum” found to the north and east of the Schladming Kaibling peak, like a ring around the peak itself.  From this “Planum” or plain with an altitude of around 1650 – 1750 m is where we can without doubt derive the name Planai from!