Q: What words are extremely hard to spell?
A: Jeff Grant, Word Ways, May, 1989, Volume 22, Number 2, pp. 107-8, 128
bouillabaisse boo-yah-baze caoutchoucin koo-choo-sin carillon(n)eur ka-rill-yon-err dyspnoea dis-nee-uh eisteddfodau ess-teth-vod-eye eschscholtzia esh-olt-see-uh homoiousia hoe-moy-ooz-ee-uh Houyhnhnm hwin-um intussuscipiens in-tuh-suh-sip-ee-uns kwashiorkor kwosh-ee-or-cor mlechchha mletch-char Nietzschean nee-chee-in Orszaggyules or-sargg-dyu-laze Phacochoerus fay-ko-key-riss pr(a)emunire pree-myu-nigh-ree Pterichthys tur-ick-thiss rijsttafel rye-stoffel Shabuoth shuh-voo-oss syssitia siss-ish-uh Takhtadjy tarc-tar-jee vichyssoise vee-shee-swahz yuffrouw yew-frou