Having the taste, smell, or appearance of eggs; containing eggs or resembling eggs in some way.
From 'egg' (Old English 'æg,' from Old Norse 'egg') plus the suffix '-y' (making it an adjective). Simple descriptive term that uses the egg itself to describe something.
The smell of 'eggy' sulfur is actually hydrogen sulfide—the same gas that makes rotten eggs stink—and interestingly, it's found in hot springs and volcanoes, so you're smelling something that comes from deep inside Earth!
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