What does ecdyson mean?
Ecdyson, more commonly spelled ecdysone in modern scientific writing, is a steroidal hormone that governs moulting and metamorphosis in insects and other arthropods. Secreted chiefly by the prothoracic glands, it rises to critical levels at key points in an insect's development, triggering the shedding of the old cuticle and the transition between life stages — larva to pupa, or pupa to adult. The name derives from the Greek 'ekdysis', meaning the act of stripping off or moulting, which also gives us 'ecdysiast', a jocular term for a striptease performer. Because ecdyson orchestrates one of nature's most dramatic transformations, it has become a central subject in developmental biology and pest-control research, since disrupting its action can halt insect growth. It remains firmly a technical term, encountered mainly in entomology and endocrinology rather than everyday speech.
nounA steroidal insect hormone, also known as the moulting hormone, that triggers moulting and metamorphosis in arthropods.
- A steroidal prothoracic-gland hormone in insects and other arthropods that initiates moulting and metamorphosis.
"Rising levels of ecdyson prompt the caterpillar to shed its skin and enter the pupal stage."
"Experiments showed that injecting ecdyson into a dormant pupa triggered premature adult development."
"Without a sufficient titre of ecdyson, the larva cannot progress to its next instar."
Rarely pluralised; when referring collectively to ecdyson and its many analogues, scientists usually say 'ecdysteroids' instead.
"Various ecdysons have been identified across different insect species."
The hormone that makes insects shed their skin gave us the word 'ecdysiast' — a polite term for a strip-tease artist.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of ecdyson
Ecdyson was coined in the mid-20th century following the isolation of the moulting hormone by German researchers, who named it after the Greek 'ekdysis' (a stripping off), formed from 'ek-' (out) and 'dyein' (to slip out of). The term entered English through German scientific literature as 'Ecdyson'. It belongs to a small family of related terms including 'ecdysis' and 'ecdysteroid', all rooted in the same Greek verb.
Related word forms
How ecdyson is actually used
A technical term used almost exclusively in entomology and endocrinology; 'ecdysone' is the more common spelling in modern scientific literature, while 'ecdyson' reflects earlier German-influenced usage.
Easily confused with ecdyson
Eclosion refers to the emergence of an adult insect from its pupal case or of a larva from the egg, whereas ecdyson is the hormone that drives moulting and metamorphosis.