gibberellin

noun Biochemistry.

1. any of a class of growth hormones occurring in fungi and plants.

noun

1. any of several plant hormones, including gibberellic acid, whose main action is to cause elongation of the stem: used in promoting the growth of plants, in the malting of barley, etc

1. Any of numerous plant hormones, especially gibberellic acid, that promote stem elongation. The seeds, young shoots, and roots of plants contain gibberellins, and they are also found in fungi.