What does derris mean?
Derris is a genus of woody climbing plants belonging to the pea family, native to Southeast Asia and the Pacific region. Its significance lies in its roots, which contain rotenone, a naturally occurring compound that is highly toxic to insects and fish yet comparatively short-lived in the environment. For well over a century, dried derris roots were exported and ground into powder — sold as 'derris dust' or 'derris powder' — providing gardeners and farmers with one of the earliest widely available botanical insecticides, long before synthetic pesticides dominated the market. The substance has also traditionally been used to stun or kill fish in rivers. Although still encountered in organic gardening discussions, derris products have been restricted or withdrawn in several countries over safety concerns, giving the word a somewhat dated, specialist flavour today.
nounA genus of tropical climbing plants native to Southeast Asia, whose roots contain the toxic compound rotenone and are used as an insecticide and fish poison.
- A genus of tropical Asian climbing plants in the legume family whose roots yield rotenone, used as an insecticide and fish poison.
- Prepared root material (powder or extract) of these plants used as an insecticide.
"The gardener dusted the crops with powdered derris root to keep the beetles at bay."
"Farmers in Malaya harvested derris root for export as a natural pesticide."
"A light application of derris dust protected the beans without harming the soil."
Rarely pluralised; usually treated as an uncountable mass noun for the powder, or left unchanged when referring to plants collectively.
"Various derrises were cultivated across the Malay archipelago."
This unassuming vine was so lethal to insects that gardeners ground its very roots into dust — and dumped it into rivers to stun fish.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of derris
The word derives from New Latin Derris, adopted as the scientific genus name, ultimately from Greek dérris, meaning a skin, hide, or casing. It shares this ancient root with medical terms built on the same Greek element, such as dermis and epidermis. The name entered English usage in the nineteenth century alongside the botanical classification and the growing trade in the plant's insecticidal roots.
How derris is actually used
Chiefly used in agricultural, horticultural, and historical contexts; treated as a mass noun when referring to the powdered preparation, but countable when naming plants of the genus.
Easily confused with derris
Dermis is the inner layer of skin, whereas derris is a genus of insecticide-bearing tropical plants.