1.   Perhaps the most agreed upon, and at the same time least understood, symbol is K for a strikeout.

2.   Echelon is perhaps the best known and least understood spy tool.

3.   Intelligence experts believe that he may have several nuclear weapons, making him the least understood of any leader with a finger on a nuclear trigger.

4.   Perhaps the least understood of the five senses, the sense of taste adds . . . well, spice to life.

5.   The least understood fiscal fact of our time is that Clinton was coaxed into balancing the budget downward.