I can see how this could work in English. I’m not sure if there are other languages in which 3/4 of a word carries more meaning. (I’m a primary English speaker, so this concern could be unfounded.)
Using a classic Latin example from Monty Python, Romani ite domum / Romanes eunt domus;
the "Roman" part of of Romanes/Romani actually carries very much meaning and the -es/-i has information that's largely orthogonal to that.
Technically the smallest indivisible unit that bears meaning is the morpheme, not the word. For example the word “cats” in English consists of two morphemes, cat+s. The first morpheme can stand on its own as a word, but the second can’t.
I don’t think you could really give an uncontroversial symbolic definition for any natural word.