hornwort

American  

[hawrn-wurt, -wawrt] / ˈhɔrnˌwɜrt, -ˌwɔrt /

noun

1. any aquatic plant of the genus Ceratophyllum, found in ponds and slow streams.

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hornwort British  

/ ˈhɔːnˌwɜːt /

noun

1. any aquatic plant of the genus Ceratophyllum, forming submerged branching masses in ponds and slow-flowing streams: family Ceratophyllaceae

2. any of a group of bryophytes belonging to the phylum Anthocerophyta , resembling liverworts but with hornlike sporophytes

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hornwort Scientific  

/ hôrn′wûrt′,-wôrt′ /

1. Any of about 100 species of small bryophyte plants belonging to the phylum Anthocerophyta. Unlike liverworts but like mosses, hornwort sporophytes have stomata. The hornwort gametophyte consists of a low thallus, out of which numerous slender, upright sporophytes tipped with sporangia grow. The sporophyte has a meristem that elongates the sporophyte with new growth, a feature that distinguishes the plant from the other bryophytes. The name of the hornworts was suggested by the hornlike appearance of the sporophytes.

2. See more at bryophyte

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Etymology

Origin of hornwort

First recorded in 1795–1805; horn + wort ²

Example Sentences

They first introduced the RbcS-STAR component into a closely related hornwort species that does not naturally form pyrenoids.

From Science Daily • Mar. 11, 2026

The green goo, found in hornwort plants, joins a host of other species honoring famous people.

From Slate • Jun. 14, 2022

Unlike the elaters observed in horsetails, the hornwort pseudoelaters are single-celled structures.

From Textbooks • Jan. 1, 2015

The short, blue-green gametophyte is the dominant phase of the lifecycle of a hornwort.

From Textbooks • Jan. 1, 2015

Grass, milfoil, water crowfoot, hornwort, starwort, horsetail, and a dozen other delicate plants, form one tangled forest, denser than those of the Amazon, and more densely peopled likewise.

From Prose Idylls, New and Old by Kingsley, Charles