This word is far from new. In the sense of something that takes place in or dates from several distinct periods of time, it’s first recorded from 1907. In 1959, Edward T Hall introduced a new meaning in The Silent Language, which became something of a buzzword from the late 1990s on.
If you’re a polychronic personality, you work happily with many things happening at one time, in a non-linear and emotional way that lets you change your plans at a moment’s notice without distress and without worrying about deadlines. It’s the opposite of the personality type called monochronic: time-driven, working in a linear and orderly way, intent on getting one job completed before starting the next.
The stimulus for the shift of polychronic from an academic environment to popular newspaper articles has been our growing understanding of the stress being suffered by office workers trying to cope with too many things at once. That has led to buzz phrases such as time poor, acceleration disorder, hurry sickness, and compression tiredness. Human-resource experts say that the monotonic personality works best in the modern workplace and that polytonic ones are at a severe disadvantage.
Traditionally, cultures are divided into monochronic (where time is regarded as linear, people do one thing at a time and lateness and interruptions are not tolerated) and polychronic (where time is seen as cyclical, punctuality is unimportant and interruptions are acceptable).
Daily Telegraph, Dec. 1999
Polychronic people ... can be more productive since they use their time to work on more than one task. A polychronic person can more easily adapt to jobs such as interpreters (listening in one language while speaking in another), or as a receptionist who acts as telephone operator and secretary simultaneously.
Business Mexico, 1 April 2002