(1)   A job in an organization
"He occupied a post in the treasury"
(2)   Physical position in relation to the surroundings
"The sites are determined by highly specific sequences of nucleotides"
(3)   A condition or position in which you find yourself
"The unpleasant situation (or position) of having to choose between two evils"
"Found herself in a very fortunate situation"
(4)   The general state of things; the combination of circumstances at a given time
"The present international situation is dangerous"
"Wondered how such a state of affairs had come about"
"Eternal truths will be neither true nor eternal unless they have fresh meaning for every new social situation"- Franklin D.Roosevelt
(5)   A complex or critical or unusual difficulty
"The dangerous situation developed suddenly"
"That's quite a situation"
"No human situation is simple"