John le Carre wrote fiction espionage novels. Espionage novels are novels which focus on a spy's life or spying in general. His most famous work is The Spy That Came In from the Cold.
The definition of a ditz is slang for someone who is silly or who seems to have scattered thinking. An example of ditz is a silly dumb person who just giggles all day. ditz. Slang a person thought of as being flighty, eccentric, silly, etc. ditz.
The hertz (symbol: Hz) is a unit derived from time which measures frequency. Frequency is how often something happens. A frequency of 1 hertz means that something happens once a second. The note Middle C (the C in the middle of the piano) is 262 Hz.