The term 'KIND OF SECRET' can be broken down into four crossword solutions: TRAD (4 letters), TRADE (5 letters), OPEN (4 letters), and STATE (5 letters). TRAD is an abbreviation of the word 'TRADE, ' which is the exchange of goods or services between two or more parties. TRADE is a verb that means to engage in the exchange of goods or services. OPEN is an adjective that describes something that is not hidden or concealed. Finally, STATE is a noun that refers to a nation or its government. Together, these four words describe a type of secret that is not completely hidden or concealed, but rather is known by some people or entities.