|1.||[ adjective ] (biology) permanently attached to a substrate; not free to move about|
"an attached oyster" "sessile marine animals and plants"
|Related terms:||vagile biology|
|2.||[ adjective ] (biology) attached directly by the base; not having an intervening stalk|
"sessile flowers" "the shell of a sessile barnacle is attached directly to a substrate"
|Related terms:||pedunculate biology|