An·guil·la (āng-gwĭl'ə, ān-) An island of the British West Indies in the northern Leeward Islands. Settled by the British in the 17th century, it was part of the self-governing colony of St. Kitts-Nevis-Anguilla until 1967, when it seceded unilaterally. A bid for full independence led to the landing of British troops in 1969. Anguilla became a dependency of Britain in 1971.