In the adjective form, it means having a glassy, translucent appearance. As a noun, it means “a thing that is clear and translucent like glass, especially a smooth sea or clear sky.”
It looks like it’s used in biology and entomology to describe things like human tissues and insect wings.
I came across it this past week in the book Solenoid by Mircea Catarescu, where it was easy to remember because he uses it a lot.
The OED entry seconds Jessie’s definitions, if you wish to take a look. The roots are Greek and Latin, for glass or crystal. You’ll find guidelines for pronunciation, too. In both British and US examples, “leen” or “line” work.
The metaphorical use for smooth, glassy water really strikes my fancy at this time of year. I hope your days are equally hyaline in the summer months ahead.
Send in useful words or metaphors, by e-mailing me (jessid -at- richmond -dot- edu) or leaving a comment below.
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