When someone deliberately links to the Rick Astley youtube music video of "Never Gonna Give You Up" on the World of Warcraft forums. It can be either a straight link or a deviating description prior to the link.

Also known as being RickRolled, Rickroll'd, or /RickRoll.

To post a misleading link with a subject that promises to be exciting or interesting, e.g. "World of Starcraft in-game footage!" or "Paris Hilton blows Busta Rhymes' dick" but actually turns out to be the video for Rick Astley's debut single, "Never Gonna Give You Up". A variant on the duckroll. Allegedly hilarious.

When you're looking for something interesting on youtube, and someone sends you a link, it's usually the video to Rick Astley's "Never Gonna Give You Up"

To disguise a link to a video of Rick Astley singing "Never Gonna Give You Up." Popularized from excessive use on 4chan and certain Internet gaming forums.

Tricking someone on the internet into watching "Rick Astley - Never Gonna Give You Up" via links through the internet. Usually masked as a youtube link, noting something completely unrelated to the video.

Never gonna give you up,
never gonna let you down,
never gonna run around and
desert you...
Never gonna make you cry,
never gonna sa-ay goodbye,
never gonna tell a lie
and hurt you.

to be shown a video of Rick Astley's "Never Gonna Give You Up" through a sly or not-so-sly link to a video on popular video sharing sites.

The act of tricking someone into clicking a YouTube or other video link to the music video of Rick Astley's "Never Gonna Give You Up".