To pour out or spread forth in abundance; to express feelings or ideas with unrestrained enthusiasm or emotion.
From Latin 'effundere' (to pour out), the same root as 'effund.' In modern usage, it often means to express feelings lavishly or without restraint.
In medicine, an 'effusion' is when fluid pours out of an organ into the body cavity—doctors borrowed the pouring metaphor to describe what happens when body fluids overflow their boundaries, just like the original Latin sense.
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