means working or connected without physical wires, typically by radio waves — as in wireless internet, phones, or early radio itself.

from A plain English compound: "wire" + the suffix "-less" (Old English -leas, meaning "without"). In the late 19th and early 20th centuries, "wireless" was the word for radio telegraphy — communication that needed no telegraph wire strung across the land — and in Britain "the wireless" long meant the radio set itself. The word slept for decades, then woke up again with networks and devices, freshly literal: still, simply, without a wire.