Mark words/phrases on pages (A,B,C) and get asorted list of them on page C

[martin.schulz]

Ist there a way/plugin that allows me to mark word/phrases on different pages and provides a widget that display a list of all marked words (of selected pages .. maybe by tag)  on an other page.

Example

Page A: I like flowers and dogs

Page B: Today we cover dogs and cats

Page C with widget for marked word of pages A and B:

• dogs
• flowers
• cats
  
  

I looked into glossary plugins but that's not really it.

Any tips?

[David at David Simpson Apps]

Labels?

[martin.schulz]

Well, not quite. 

1. theese pages already have labels for other reasons
2. having dozens of "marked" words on each page would end up in a big label mess
3. some of the words are not suitable for beeing a label which would end up in cut off information
4. one would need to constantly match content and labels which gives it an other point of failure