Prajalpa means talking all nonsense. Suppose politics."What Mr. Nixon did yesterday, or what did he say?" So what interest we have got in Mr. Nixon? We shall not waste our time talking this politics, that politics, this sociology, this cinema, this affair, no. We have nothing to do with that. That is called prajalpa, unnecessary talking.Talking means decreasing your duration of life. Talking. So why should you decrease your life unnecessarily? Every moment you have to utilize, "Whether it is used for Krsna?" This is sadhana. This is sadhana, practice. Unnecessary talking, unnecessary making enemies. Unnecessarily, "You are my subordinate; I am your master." Who is master? Everyone is subordinate to Krsna. Nobody is master. Why you talk unnecessarily?
Srila Prabhupada in Srimad-Bhagavatam 1.16.6 -- Los Angeles, January 3, 1974