apogeotropism

from The Century Dictionary.

• noun A tendency to turn or bend in opposition to gravity, or upward and away from the earth, as opposed to geotropism (which see): said of stems or other parts of plants. Darwin.

from the GNU version of the Collaborative International Dictionary of English.

• noun The apogeotropic tendency of some leaves, and other parts.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun An apogeotropic tendency.