Adjective: (Latin: perspicere, to see through) clear in a statement or expression; easily understood.
Adjective: intended as instructional. Noun: a book, speech, essay, etc., that is protreptic.
Noun: The branch of medicine that deals with the diseases and problems of old age.
Noun: the study of the process of aging and old age in general.
Noun: a state, society, or group governed by old people; government based on rule by old people.
Pierre Guesnon is a retired engineer who founded and ran an engineering company in Boston for many years, until he retired fifteen years ago. Since then, he has lived most of each year on Marco Island. He is married to an Australian, Margaret Guesnon, whom he met in London and married in Sydney. They have two daughters. Pierre has had a lifelong interest in words and language.