Dictionary.com
Thesaurus.com

hydrology

American  
[hahy-drol-uh-jee] / haɪˈdrɒl ə dʒi /

noun

  1. the science dealing with the occurrence, circulation, distribution, and properties of the waters of the earth and its atmosphere.

  2. hydrogeology; geohydrology.


hydrology British  
/ ˌhaɪdrəˈlɒdʒɪk, haɪˈdrɒlədʒɪ /

noun

  1. the study of the distribution, conservation, use, etc, of the water of the earth and its atmosphere, particularly at the land surface

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

hydrology Scientific  
/ hī-drŏlə-jē /
  1. The scientific study of the properties, distribution, and effects of water as a liquid, solid, or gas on the Earth's surface, in the soil and underlying rocks, and in the atmosphere.


Other Word Forms

Etymology

Origin of hydrology

First recorded in 1755–65; hydro- 1 + -logy

Explanation

Hydrology is the science that has to do with water on our planet and in the atmosphere, including how water moves, where it exists, and its specific properties. Hydrology is a branch of geology, the study of the earth that focuses specifically on the planet's water systems. This scientific specialization involves analysis of our water's quantity, quality, and location based on the water cycle. Scientists who study hydrology are known as hydrologists, and their work includes testing water samples for contamination, predicting floods and droughts, and making sure our drinking water is clean. The word hydrology comes from the Greek roots hydro-, meaning "water," and -logy, meaning "study of."

Keep Reading on Vocabulary.com

Vocabulary lists containing hydrology

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

In the blistering heat of 2026, where climate records are tumbling all over the world, the river is under attack on two fronts, said David Kreamer, a hydrology professor at the University of Las Vegas.

From Barron's Aug. 27, 2026

It is important to note, though, that many other factors affect the risk of flooding including land use, groundwater extraction, local hydrology and preceding conditions.

From BBC Feb. 18, 2026

It’s possible, Larson said, “that the hydrology is just getting so bad right now that people are getting really nervous, and that’ll push people to the table as they get worried.”

From Los Angeles Times Jan. 22, 2026

The air will be filled with dust while patterns for hydrology and drainage will be altered, perhaps with unanticipated consequences.

From Salon Sep. 19, 2024

Both of us have been trained in hydrology and have made many dives before.

From The Thirst Quenchers by Rick Raphael

Vocabulary.com logo
by dictionary.com

Dictionary.com's Learning Companion

Go beyond just looking up words.
Remember them forever with VocabTrainer.

Start training