tidal

adjective

tid·​al ˈtī-dᵊl 

1

a

: of, relating to, caused by, or having tides

tidal cycles

tidal erosion

b

: periodically rising and falling or flowing and ebbing

tidal waters

2

: dependent (as to the time of arrival or departure) upon the state of the tide

a tidal steamer

tidally

ˈtī-dᵊl-ē 

adverb

Examples of tidal in a Sentence

Recent Examples on the Web

Underwater grasses in the Chesapeake Bay and its tidal tributaries increased 13% in 2025, covering almost 5,000 more acres in Maryland's portion of the Bay, state officials reported. — Karl Hille, Baltimore Sun, 15 Sep. 2026

Flocks of Hudsonian godwits (the smallest of the four godwit species and the least well known) spend from roughly early October to April in and around the tidal mudflats there. — Rivka Galchen, New Yorker, 14 Sep. 2026

The annual underwater grass survey is carried out by the Virginia Institute of Marine Science (VIMS), which maps submerged aquatic vegetation, or SAV, throughout the Chesapeake Bay and its tidal tributaries. — Michelle Richardson, CBS News, 8 Sep. 2026

The World Meteorological Organization (WMO) estimates that 300,000 to 500,000 people died, most from the surge flooding coastal islands and tidal flats. — Kaif Shaikh, Interesting Engineering, 6 Sep. 2026

Word History

First Known Use

1807, in the meaning defined at sense 1a

Phrases Containing tidal

• tidal wave

Rhymes for tidal

• bridal
• bridle
• idle
• idol
• idyll
• seidel
• sidle
• widal
• apsidal
• subtidal
• bactericidal
• insecticidal

Kids Definition

tidal

adjective

tid·​al ˈtīd-ᵊl 

: of or relating to tides : rising and falling or flowing and ebbing at regular times

Medical Definition

tidal

adjective

tid·​al ˈtīd-ᵊl 

: of, relating to, or constituting tidal air

interference with the normal tidal exchange of the lungs

—F. R. Mautz & R. M. Hosler