monocyclic

from The American Heritage® Dictionary of the English Language, 5th Edition.

• adjective Having a single cycle, as of activity or development.
• adjective Biology Having a single whorl, as certain flowers and the shells of certain invertebrates.
• adjective Chemistry Having a molecular structure with only one ring.

from The Century Dictionary.

• Disposed in a single whorl or circular series, as the stamens in many flowers.
• Of or pertaining to the Monocyclia.
• In botany, living only one season; annual: opposed to dicyclic. See dicyclic, 3.
• In electricity, pertaining to a single-phase alternating-current system of electric distribution, which utilizes an auxiliary electromotive force (the teaser electromotive force) out of phase with the main electromotive force, and wattless, that is, supplying no power or practically no power, but only wattless currents. See wattless.
• Of or pertaining to a monocycle. See monocycle, 2.
• A mechanical system within which only stationary movements in closed curves occur and between the portions of which only conservative forces are active.
• See monocyclic, 4.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• adjective Having a single cycle of development or activity.
• adjective chemistry Having a single ring of atoms in the molecule; such as benzene or cyclopropane.