undefended

British  

/ ˌʌndɪˈfɛndɪd /

adjective

1. not having people to provide resistance against danger, attack, or harm

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Example Sentences

Canada and the US share deeply integrated economies, a long-standing security partnership and the longest "undefended" border in the world.

From BBC

Canada and the US share the world's longest undefended border.

From BBC

It didn’t take long for the Stars to score from there, with Robertson setting up in the slot undefended, taking a pass and wristing the puck past Grubauer to make it 2-0.

From Seattle Times

At Amnya, her team also noted a possible sign of social stratification, another development often linked to agriculture: a cluster of houses that sat, undefended, outside the palisade.

From Science Magazine

Archival: Germany's air arm, better known as the Luftwaffe blazes the trail for the opening attacks on Holland, Belgium and tiny undefended Luxembourg.

From Scientific American