Sentence:  There now remains the fourth side of the square, which is devoted to the state and <WSD>semi-state</WSD> carriages. The <WSD>semi-state</WSD> carriages, eleven in number, are chiefly of modern make. 
Meaning of the word marked with <WSD> tags:  ceremonial, but somewhat less ornate, formal, or prestigious than would be classed as "state"