Weasel
A small, slim hunter that can enter narrow spaces — appetite that finds a way through any gap.
A weasel in a dream is the dream's image of appetite that finds its way through any gap. The weasel is small enough to follow prey down into burrows and is remarkable for the size of what it will take on. The dream brings the weasel when something in your life — a habit, a person, a slow-growing temptation — is small enough to slip through every guard you have set and is taking more than the size of it would suggest. A weasel caught at the chicken-house door is the dream telling you the entry has been spotted in time. A weasel already inside, with the work done, is the dream noting that the gap was always there and the small persistent hunter found it without difficulty.