English
hydrotropism
From hydro- + -tropism.
Proto-Indo-European *wed- ‘water’
Proto-Indo-European *wódr̥ ‘water’
Proto-Hellenic *údōr ‘water’
Ancient Greek ὕδωρ ‘water’
English hydro
Proto-Indo-European *trep- ‘to turn’
Ancient Greek τρέπω ‘turn, divert, turn back, rout an enemy’
Ancient Greek τρόπος ‘a turn, way, manner, style, a trope or figure…’
Latin tropus ‘a figurative use of a word, a trope’
English tropism
Today it means
noun The movement of a plant (or other organism) in response to water, either towards or away from water.
Language periods are conventional ranges, not dates for this word.
Etymograph / hydrotropism