A similar question reminds me: When giving talks, I often want to refer to the work of Henry Crapo. I have asked several mathematicians, and none of them were sure how to pronounce his last name. Any help?
My name is Martin Crapo, and have always pronounced it Cray-poe. The name evolved from Crapaud and Crepeaux. Pierre Crapo was the French boy who stowed away on his brothers French Merchant ship in the late 1600's. His brother initially refused to bring him on his trip to America from France, so young Pierre boarded the ship unbeknownst to his brother and hid. After a few days, he came out from hiding. Seeing a dilemma, his brother took him along. Arriving in Cape Cod, the ship was caught in a storm and was wrecked upon the rocks. Strangely Pierre, his Captain brother and about 3 sailors survived. When his brother earned enough money to return to France, he apprenticed his brother Pierre to someone for work, saying that he would soon return to get him. He never returned. Pierre was the beginning of the Crapo's in America. My contact is Crapo007@gmail.com
It seems that the one of the people in Wikipedia, Governor Henry Howland Crapo of Michigan, has exactly the same name as the mathematician Henry Howland Crapo who got a PhD from Rota and eventually moved to France. I conjecture that it is not a coincidence. The latter Crapo is still alive, I think, because he submitted a paper to the arXiv himself in April of this year. So you could ask him how to pronounce his name, and about his genealogy.
The answer to the first will presumably be what Jason Dyer said, Cray'-Poe (as in Seymour Cray and Edgar Allan Poe). It is true that the name is originally a French word, but it is an entirely American name. According to the reference, the first Crapo was a French castaway who was found on Cape Cod in the 17th century. He was nicknamed crapaud (toad) just because he was French.
Might I add, somewhat nostalgically, that the amusing homonymy was a “running joke” between my dear, departed friend Henry and yours truly over the course of our extensive epistolary relationship. So it was that I playfully dubbed his fantastic, impressive home in La Vacquerie: “Toad Hall” – (an allusion to Kenneth Grahame’s marvelous tale “The Wind in the Willows”… - Edward Lamb
Wikipedia says it's like "halo."