In popular cultures, "Extraterrestrials" are life forms — especially intelligent life forms— that are of extraterrestrial origin (often also called "aliens").
Famous quotes containing the word life:
“O life unlike to ours!
Who fluctuate idly without term or scope,
Of whom each strives, nor knows for what he strives,
And each half lives a hundred different lives;
Who wait like thee, but not, like thee, in hope.”
—Matthew Arnold (1822–1888)