What do the following words have in common?

SUIT
LATE
CLOSE
CONDO
ASPIRIN

Answers:

Each word can be changed into a new one by adding a single letter at the end of the word:
 
SUITE
LATEX
CLOSET
CONDOR
ASPIRING 

Note: Some other, more familiar words, which follow this pattern are:

APE(X)
HEAR(T)
HEART(H)
PLUM(B)(P)
NIGH(T)
THOUGH(T)