4. The actual presence or meeting of any body of men in their seats, clothed with authority to transact business; a session; as, a sitting of the judges of the King's bench, or of a commission. The sitting closed in great agitation. (Macaulay)
6. A brooding over eggs for hatching, as by fowls. The male bird . . . Amuses her [the female] with his songs during the whole time of her sitting. (Addison) Sitting room, an apartment where the members of a family usually sit, as distinguished from a drawing-room, parlor, chamber, or kitchen.