It is but the spelling and also the initial doe not add up?
If you look closely at the initial after Mary, I think it's an 'A' rather than a 'D'. She may have been Mary Ann. The householder who filled in the form (Pearson) probably couldn't spell Reilly correctly and also maybe knew her as O'Reilly.
There were many spelling errors on the 1901 and 1911 Irish census forms and the transcribers for the online website spelled the names exactly as they were written.