The term 'Kind of Balloon' can be broken down into three crossword solutions: LEAD (4 letters), TRIAL (5 letters), and HOTAIR (6 letters). LEAD balloons are a type of balloon made from LEAD foil, which is used for scientific experiments due to its ability to remain in the air for long periods of time. A TRIAL balloon is a metaphor for a test or experiment, usually used in politics, to gauge public opinion on a certain issue. Hot air balloons are the most common type of balloon, filled with heated air and used for recreational purposes.