Meaning: Its source is sidan eg, an Old English name meaning "Wide meadow."

Narrative: Some have derived this surname from the Norman French place name St. Denis. However, the documents supporting this derivation have been denounced as forgeries.

Why would such documents be forged? Perhaps we can find our explanation in the one-time fashion among British aristocrats of tracing their family lines back to the Norman French conquerors of 1066.