relating to or produced by or consisting of molecules; "molecular structure"; "molecular oxygen"; "molecular weight is the sum of all the atoms in a molecule"
the act of leaving secretly or without explanation
the event of passing out of sight
ceasing to exist; "he regretted the disappearance of Greek from school curricula"; "what was responsible for the disappearance of the rainforest?"; "the disappearance of resistance at very low temperatures"
impossible or difficult to perceive by the mind or senses; "an imperceptible drop in temperature"; "an imperceptible nod"; "color is unperceivable to the touch"