The oxygenated essential oils may be either alcohols, aldehydes, ketones, acids, esters, or phenols, derived from either five-membered or six-membered closed-ring hydrocarbons.
Thatcher, Roscoe Wilfred, The Chemistry of Plant Life(2010)
adj of a chemical compound having a ring with five members
Syn
5-membered membered
having members; normally used in chemistry in combination with a number