hydrotropism

Noun

hy=drot=ro=pism

CIDE DICTIONARY

hydrotropism, n.

A tendency towards moisture. [1913 Webster]
In a broader sense, any curvature or turning induced in certain growing plant organs under the influence of moisture.
" When the movement is toward the moisture, as is the case in most roots, the phenomenon is called positive hydrotropism; when away from the moisture, as in the case of hyphae of certain fungi, negative hydrotropism." [Webster 1913 Suppl.]

hydrotropism, adj. a tendency of plant roots etc. to turn to or from moisture.

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