(Radar) A spot of light on a radar screen, showing the position of a reflecting surface, such as an airplane or ship. Note: this sense is also used metaphorically to mean a barely perceptible object;, Kennedy's candidacy was a mere blip on Humphrey's radar screen until he won the West Virginia primary. This is the probably origin of sense 3.
A short upward or downward deviation from a trend line on a graph, especially in a plot of some variable, such as an economic variable, against time; as, a brief blip upward in the unemployment rate.
Something small or insignificant.
A brief interruption in the continuity of a recorded or transmitted signal; as, there is a blip on my CD of Beethoven's ninth.