Scientists trap krypton atoms to form one-dimensional gas

In the jargon (at least in "low energy" physics and related fields), 'one-dimensional' often means that only one spatial dimension is relevant to the behavior of the system rather than that the system is only one-dimensional in terms of spatial extent. In that sense, a string of perls could be considered one dimensional if you care only about the motion of the perls along the string but not the motion of the string itself, even if the string is curved in 3D space, or the pearls are 3D objects.

This is also true of higher dimensions. For example there are some '2D' materials that are several atoms thick, but as far as the behavior of electrons is concerned the 'out of plane' direction is not important.

> i guess the "1D" short hand is well understood within the community.

Yes, this refers to systems where only one dimension is important for the physics of the system.

Can there be anything in the real world that is "literally 1d"? I would think not.