Here's how the root word plays out in various words:
* Distinguish: To perceive or recognize a difference.
* Extinguish: To put out a flame or light, thereby making it disappear.
* Distinguished: Marked by excellence or eminence, standing out from others.
* Indistinguishable: So alike that it's impossible to tell the difference.
Essentially, the root "-tinguish" highlights the act of making something stand out or clearly separate from its surroundings.