southernmost

from WordNet (r) 3.0 (2006)

southernmost
    adj 1: situated farthest south; "Key West is the southernmost
           city in the continental United States" [syn:
           {southernmost}, {southmost}]

from The Collaborative International Dictionary of English v.0.48

Southernmost \South"ern*most`\, a.
   Farthest south.
   [1913 Webster]

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