phi-phenomenon

American  

[fahy-fi-nom-uh-non, -nuhn] / ˈfaɪ fɪˌnɒm əˌnɒn, -nən /

noun

Psychology.

plural

phi-phenomena

1. motion perceived by a subject, especially the illusion of movement produced when stationary stimuli, as pictures or lights, are presented in rapid succession and are sometimes in slightly different positions.

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phi-phenomenon British  

/ ˈfaɪfɪˌnɒmɪnən /

noun

1. the illusion that when two lights are rapidly turned on and off in succession something appears to move backwards and forwards between them while the lights stay stationary

2. a similar illusion in which one light appears to move smoothly backwards and forwards

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Etymology

Origin of phi-phenomenon

First recorded in 1925–30