Pyramid words

What are Pyramid words:

A pyramid word contains a single occurrence of one letter, two of another letter, three of the next, etc. The longest examples have four occurrences of the most common letter. Common examples are banana, papaya, sleeveless, deadheaded and sereneness. Others include rememberer, restresses, chachalaca, kotukutuku, susurruses and Sassanians. In addition, Tennessee's and peppertree have been cited by Richard Lederer, with an analysis of some other interesting properties of the latter.