Question

As atoms bond covalently, the mixing of two or more atomic orbitals of similar energies is known as what

Answer 1

That process is called orbital hybridization (or simply hybridization) — e.g., mixing s and p orbitals to give sp, sp2, sp3 hybrids (C in CH4 is sp3, in C2H4 sp2, in C2H2 sp).