entrainment

[ en-treyn-muhnt ]

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.

Word History and Origins

Origin of entrainment¹

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

Example Sentences

Following a 4-week entrainment period, the researchers analyzed the behavior and genetic expression patterns of the snails in darkness at a constant temperature of 23°C. Among the snails from non-tidal areas, there were no significant differences in the intensity of the circadian and circatidal rhythms between the two groups.

From Science Daily

The research team proposes that the entrainment of these neurons under ketamine could increase the release of the beneficial peptide, as observed when these cells are stimulated in experiments.

From Science Daily

One is to flash their light in close proximity and time to another male, a behavior known as “entrainment.”

From Science Magazine

A section of his book entitled "Contagion and Dynamic Entrainment" refers to a phenomenon observed in physics: "Dynamic entrainment" is what happens when you put several metronomes, swinging out of sync, together on the same board.

From Salon

There's a general principle at work here: "By exporting instability to France during the Late Medieval Crisis England was able to delay entering its own time of troubles," or to return to his guiding metaphor, this averted "dynamic entrainment" rather than causing it.

From Salon