Real World Function CH1 by Zekai function

For my Real World Function Project, my topic was words and numbers of letters. The domains are the words and the ranges are the numbers of letters. Each word is unique. For this relation to be a function, each word only has one number of letters. My independent variables are words and dependent variables are numbers of letters. For this relation to be not a function, one word has two numbers of letters. That is impossible. For example, I have word "Duck". "Duck" was formed by four letters. Each word is unique. So its numbers of letters should be unique. But then "Duck" has seven letters. That is impossible. So the function was failed.