eicosanoid
noun
ei·cos·a·noid ī-ˈkō-sə-ˌnȯid 
: any of a class of compounds (such as the prostaglandins) derived from polyunsaturated fatty acids (such as arachidonic acid) and involved in cellular activity
Example Sentences
Recent Examples on the Web Polyunsaturated oils from corn, safflower and soybean contain lots of omega-6 fatty acids, which are precursors to inflammatory compounds known as eicosanoids. 
Dorothy Kieffer, sacbee.com, 29 May 2017
Dorothy Kieffer, sacbee.com, 29 May 2017 Word History
Etymology
eicosa- containing 20 atoms (from Greek eikosa- twenty, from eikosi) + -noic, suffix used in names of fatty acids (from -ane + -oic) + -oid entry 1 — more at vigesimal
First Known Use
1980, in the meaning defined above
Medical Definition
eicosanoid
noun
ei·co·sa·noid ī-ˈkō-sə-ˌnȯid
: any of a class of compounds (as the prostaglandins, leukotrienes, and thromboxanes) derived from polyunsaturated fatty acids (as arachidonic acid) and involved in cellular activity