Word Groupings

There are word groups, like the two major cities in Kenya, where whichever of the two I think of first, I'm totally stumped on the other one.  So, if I think of Nairobi first, Mombasa will be brain-locked.

Another one is the group of 3 rivers which run through Pittsburg.  I always remember the Ohio, but then only one of the other two, Monongahela and Allegheny.

Another two are foreign words.  Rulau is a Konkani word for what pretty much every other Indian language calls upma.  I prefer the Konkani word for a number of reasons, it sounds better, my in-laws are Konkani, etc.  But the word which comes into my head is usually upma and then rulau is locked out, also very hard to find since Konkani is an extremely niche language in India.  The word is for a savory dish made from what we call cream of wheat.