Definition of "Sitting" :

noun: the act of assuming or maintaining a seated position

"He read the mystery at one sitting."

noun: (photography) the act of assuming a certain position (as for a photograph or portrait)

"He wanted his portrait painted but couldn't spare time for the sitting."

noun: a session as of a legislature or court

noun: a meeting of spiritualists

adjective: (of persons) having the torso erect and legs bent with the body supported on the buttocks

adjective: not moving and therefore easy to attack

"A sitting target."