The phrase “waxes and wanes” is a common idiom used to describe any phenomenon that undergoes a cycle of growth and decline. This pairing of verbs encapsulates the idea of constant, predictable fluctuation rather than a static state or a one-time event. The expression communicates a dynamic process of increase followed by decrease, stemming from a specific and ancient astronomical observation.
Defining the Cycle of Growth and Decline
The meaning of the complete phrase is rooted in the individual definitions of the two Old English verbs. The verb “wax” comes from the Old English word weaxan, meaning to grow, increase, or become larger. When something is said to “wax,” it is gaining in size, strength, number, or intensity. For instance, a person might “wax eloquent” when their speech becomes more expansive and passionate.
Conversely, the verb “wane” carries the opposite meaning, signifying to decrease, diminish, lessen, or fade away. Something that is “on the wane” is in a state of gradual reduction or decline toward an endpoint.
When the two verbs are combined, they describe an alternating process of strengthening and weakening. To say something “waxes and wanes” implies it moves through a natural, repeating cycle, never reaching a permanent peak or trough. This suggests an ongoing, rhythmic pattern of rise and fall, applicable to any fluctuating condition.
The Astronomical Source: Lunar Phases
The origin of the phrase is directly tied to the appearance of the Moon as it orbits the Earth. Ancient observers charted the Moon’s visible shape, which appeared to grow and shrink over the course of its cycle. This observation led to the terms “waxing” and “waning” being adopted to describe these celestial changes around the 14th century.
The Moon does not produce its own light; its visibility is determined by the portion of its surface illuminated by the Sun that is visible from Earth. The lunar cycle begins with the New Moon, when the Moon is positioned between the Sun and Earth, making the side facing us unlit and invisible.
The “waxing” phase covers the approximately 15-day period from the New Moon to the Full Moon. During this time, the illuminated sliver visible from Earth gradually increases in size, moving through the phases of waxing crescent and waxing gibbous. When the Moon reaches the Full Moon phase, its entire visible face is illuminated, marking the peak of apparent growth.
Following the Full Moon, the Moon enters its “waning” phase, which lasts until the next New Moon. In this stage, the sunlit portion visible from Earth begins to shrink, moving through the waning gibbous and waning crescent phases. The entire process takes about 29.5 days, providing a reliable measure of cyclical time that cemented these terms in language.
Metaphorical Uses of Waxes and Wanes
Due to its clear astronomical origin, the phrase was adopted to describe any non-physical phenomenon that behaves in a cyclical manner. The idiom is used to describe fluctuations in abstract concepts, providing a vivid comparison to the reliable, rhythmic nature of the Moon’s cycle.
The popularity or political influence of a public figure is often said to wax and wane, reflecting alternating periods of high support and low approval. Similarly, a person’s enthusiasm or interest in a long-term project might wax and wane as they encounter success or challenges.
In the context of health, the phrase describes illnesses or chronic conditions where symptoms fluctuate in severity. The intensity of pain or the frequency of episodes may increase (wax) and then decrease (wane), creating a pattern of remission and flare-ups. This application emphasizes that the changes are part of a natural, ongoing pattern of rise and fall.