phenology

American  

[fi-nol-uh-jee] / fɪˈnɒl ə dʒi /

noun

1. the science dealing with the influence of climate on the recurrence of such annual phenomena of animal and plant life as budding and bird migrations.

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phenology British  

/ fɪˈnɒlədʒɪ, ˌfiːnəˈlɒdʒɪkəl /

noun

1. the study of recurring phenomena, such as animal migration, esp as influenced by climatic conditions

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phenology Scientific  

/ fĭ-nŏl′ə-jē /

1. The scientific study of cyclical biological events, such as flowering, breeding, and migration, in relation to climatic conditions. Phenological records of the dates on which seasonal phenomena occur provide important information on how climate change affects ecosystems over time.

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Other Word Forms

• phenological adjective
• phenologically adverb
• phenologist noun

Etymology

Origin of phenology

First recorded in 1880–85; contracted variant of phenomenology, with restriction to climatic phenomena

Explanation

Phenology is the science of seasonal cycles and the way they're affected by climate and habitat. Observing the movement of migrating birds, or noting when the leaves start changing color in the fall, is all part of phenology. You dabble in phenology yourself if you notice changes to the natural world in spring: plants with early blossoms, the first bees of the season, unfamiliar birds on your birdfeeder. Phenology is sometimes called "nature's calendar," but because it's sensitive to alterations in the climate, it's constantly changing. Global warming means that spring is earlier, winter is shorter — and phenology keeps an eye on how different plants and animals respond. The Greek root of phenology means "bring to light."

Example Sentences

The timing of seasonal activity in plants and animals is known as phenology and is collected by a network of volunteers coordinated by the Nature's Calendar citizen science project.

From BBC • Jul. 13, 2025

"The unchanging ice phenology of Yellowstone Lake stands in stark contrast to similar lakes in the Northern Hemisphere."

From Science Daily • Apr. 16, 2024

The phenomenon in which normally green leaves transition into shades of red, orange, yellow and eventually brown is known officially as "leaf phenology," which some people eagerly anticipate each year.

From Salon • Nov. 18, 2023

The study of the way species time their behavior with Earth’s cycles is called phenology.

From Scientific American • Mar. 22, 2023

Heat accumulation is one of the main ways to predict life cycle transitions in plants and animals, according to the phenology network.

From Washington Post • Feb. 1, 2023