Definition: (photography) the act of assuming a certain position (as for a photograph or portrait)
Usage: he wanted his portrait painted but couldn't spare time for the sitting
Similar words: motility, motion, move, movement
Definition: a change of position that does not entail a change of location
Usage: the reflex motion of his eyebrows revealed his surprise; movement is a sign of life; an impatient move of his hand; gastrointestinal motility