-trophic Also -trophy, -trophism, -troph, and -trophe.
[Greek trophikos, from trophē, nourishment.]
Terms ending in -trophic are adjectives: a heterotrophic (Greek heteros, other) organism derives its nutritional requirements from complex organic substances; a lake that is eutrophic (Greek eu, well) is rich in nutrients and supports many plants, whose decomposition kills animal life by depriving it of oxygen; an organ that is hypertrophic (Greek huper, over, beyond) has grown because its cells have increased in size, not because their number has risen.
Nouns in -trophy and -trophism name the state or condition associated with such adjectives, the former being more common than the latter: atrophy (Greek a-, not), wasting away of body tissue or an organ (adjective atrophic); dystrophy (Greek dus-, bad), a disorder in which an organ or tissue of the body wastes away (adjective dystrophic).
Nouns in -troph refer to instances of the state or condition: auxotroph (Latin auxilium, help), a mutant organism that requires a particular additional nutrient which the normal strain does not. Some can appear spelled -trophe: oligotrophe, an instance of a lake which is relatively poor in plant nutrients and containing abundant oxygen in the deeper parts, from Greek oligoi, few.
Apostrophe, catastrophe and their relatives derive instead from Greek strophē, turning.