import re
 
pattern = r"(?<!\S)(?:(?!\b(?:at|on|in|adjoining)\b)[^\n\d])*? street\b"
 
s = ("flat 14, 24-34 barrington street, London\n"
            "23 the honourable lord barrington's street, London\n"
            "23 the honourable lord barrington's street, 42 the dishonarable baron lordington's street, London\n"
            "land to the south of barrington street, London\n"
            "plot 12 on barrington street, London")
 
print(re.findall(pattern, s))

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