Elaiosome (e-lay-o-zome): (Greek: elaion=oil + soma=body) literally meaning ‘oil body.’* A structure on the surface of a seed that secretes and stores oil, usually as an attractant to ants, which assist in seed dispersal.**
Ants drag the seeds underground to feed their colonies on the elaiosomes. In this way, the seeds become ‘planted’ and ready to grow. Many plants offer elaiosomes as a means to seed dispersal, some common examples are violets, dicentra, and trilliums (pictured above: Trillium recurvatum, the elaiosomes are the white substance attached to the top of the seeds).
*Kesseler, R. & Stuppy, W. (2006). Seeds: Time capsules of life. Buffalo: Firefly Books.
**Allaby, M. (2006). A dictionary of plant sciences (Revised ed.). Oxford: Oxford University Press.