The spelling of the word "ZEO" can be confusing as it is not a commonly used word. The correct pronunciation is /ziːəʊ/. The first two letters "ZE" are pronounced as /ziː/, which is like the sound of the word "see" but with a longer "ee" sound. The last letter "O" is pronounced as /əʊ/, which is like the sound in the word "go" but with a longer "o" sound. So altogether, the pronunciation of "ZEO" is /ziːəʊ/.