| any of a class of insect and plant hormones acting to inhibit the molting of a juvenile insect into its adult form. |
| juvenile hormone n. A hormone in arthropod larvae that inhibits ecdysone, thereby preventing molting and the development of larvae into adults until its level drops. |
juvenile hormone
a hormone in insects, secreted by glands near the brain, that controls the retention of juvenile characters in larval stages. The hormone affects the process of molting, the periodic shedding of the outer skeleton during development, and in adults it is necessary for normal egg production in females. See also thoracotropic hormone.
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