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"
a bodily passage or tube lined with epithelial cells and conveying a secretion or other substance; "the tear duct was obstructed"; "the alimentary canal"; "poison is released through a channel in the snake's fangs"
a continuous tube formed by a row of elongated cells lacking intervening end walls