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adj. Having two or more atomic rings in a molecule.

adj. Having two or more rings of atoms in the molecule.

n. Such a compound

Having many rounds, turns, or whorls, as a shell.

In electricity, noting a system of electric distribution by alternating currents, in which the energy maxima of the flow of power of the different circuits overlap so as to give a total flow of power of constant intensity. This is the case in a symmetrical or hemisymmetrical polyphase system. See polyphase.

In chem., containing more than one atomic ring in the molecule.

"Sweden deserves mention, namely that certain polycyclic hydrocarbons initiating mouse tumors put a specific, antigenic mark on these, which persists despite repeated transplantation of the growths."

polycyclic hydrocarbon   

monocyclic    tricyclic    bicyclic   

terpene    heterocyclic    nonpolar    acyclic    steroidal