sessile

[ ses-il, -ahyl ]

adjective

1. Botany. attached by the base, or without any distinct projecting support, as a leaf issuing directly from the stem.
2. Zoology. permanently attached; not freely moving.

sessile

/ ˈsɛsaɪl; sɛˈsɪlɪtɪ /

adjective

1. (of flowers or leaves) having no stalk; growing directly from the stem
2. (of animals such as the barnacle) permanently attached to a substratum

sessile

/ sĕs′īl′ /

1. Permanently attached or fixed and not free-moving, as corals and mussels.
2. Stalkless and attached directly at the base, as certain kinds of leaves and fruit.

Derived Forms

• sessility, noun

Other Words From

• ses·sil·i·ty [se-, sil, -i-tee], noun
• pseudo·sessile adjective
• sub·sessile adjective

Word History and Origins

Origin of sessile¹

1715–25; < Latin sessilis fit for sitting on, low enough to sit on, dwarfish (said of plants), equivalent to sess ( us ) (past participle of sedēre to sit ¹ ) + -ilis -ile

Word History and Origins

Origin of sessile¹

C18: from Latin sēssilis concerning sitting, from sedēre to sit

Example Sentences

Researchers learned that sessile invertebrates -- those that stay in one place, such as mussels and barnacles -- became more abundant during the study period, while seaweed species like kelps declined.

From Science Daily

Studies of other kinds of deep-sea disturbances, including deep-sea trawling and oil and gas operations, have suggested that sessile animals are especially vulnerable, sometimes taking decades to recover.

From Scientific American

But unlike most others in that group, it does not undergo metamorphosis from a free-swimming larva to a fixed-to-the-bottom, or sessile, adult.

From Scientific American

But many coastal species are sessile – meaning they are stuck to rocks for all their adult lives.

From Salon

Miller weaves an improbable but compelling theory of how his study of sessile sea squirts influenced the United States’ painful legacy of forced sterilization.

From New York Times