"that Bill" 这个短语可能指的是多种情况，具体含义取决于上下文。以下是一些可能的解释：
1. 指示代词：在句子中，"that" 是一个指示代词，用来指代前面提到的 "Bill"。例如：
"I saw that Bill at the store yesterday."
"That Bill is my uncle."
2. 特定的人名："Bill" 可能是一个人的名字，"that" 表示特定的某个人。例如：
"I need to talk to that Bill about the project."
"That Bill is responsible for the company's finances."
3. 泛指：有时 "that Bill" 可能只是泛指一个名叫 Bill 的人，而不是指特定的某个人。例如：
"That Bill always has great ideas."
"That Bill is a good friend of mine."
