entrainment

American  

[en-treyn-muhnt] / ɛnˈtreɪn mənt /

noun

1. the act or fact of trapping bubbles in a liquid.

   A notorious problem in some ink-jet printing systems is the entrainment of tiny air bubbles in the ink during operation.

2. the act or fact of being drawn into a current or flow.

   Fish screens have proven reliable at preventing fish entrainment into watercourses diverted for agricultural use.

3. the synchronization of different rhythmic cycles that interact with each other.

   In individuals with sleep-wake disorder, continued treatment with medication was required to maintain entrainment of the circadian rhythms of melatonin and cortisol in the body.

4. Chemistry. the carrying along of a substance in a moving fluid, as drops of liquid in a vapor during evaporation or distillation.

   The research studies the physical processes determining droplet entrainment in turbulent gas flow over a liquid layer in pipes and channels.

5. Meteorology. the transfer of air from the surrounding atmosphere into an organized air current.

   During a hurricane the temperatures in the upper atmosphere depend partly on the entrainment of drier or cooler air from outside the vortex.

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Etymology

Origin of entrainment

First recorded in 1830–40, for an earlier sense; from French entraînement, equivalent to entrain ² ( def. ) + -ment ( def. )