A phrase used in Ireland meaning to stalk or to creep. Originates from an old folklore tale of an old woman named Maude ("Máudé Gránte" in Irish - defines a nosy old woman) who used to be very nosy in her friends private business.
Also is used to describe a large breasted woman, or very precisely, a large breasted creepish woman.
That girl wont leave me alone, she keeps in at my business and wont piss off! "what a maude!"