The best replacement for orbitals is orbits.

The best alternatives to orbitals are rated as following:
★★★★★  orbits
★★★  shells
★★  atomic orbitals
★★  energy levels
★  molecular orbitals

Your alternative for orbitals is not listed? Suggest!
Speaking about orbitals, one probably shouldn't forget about lowest energy.

Other search terms related to orbitals and their ratings are:
★★★★★ lowest energy
You have in mind a companion for orbitals and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of orbitals in all years. Click on graph for more.
orbitals
orbits
shells