Merriam Webster has one pronunciation for the word lackadaisical, but often people pronounce it laxadaisical.
“I would guess that what’s happened here is that speakers have reinterpreted lackadaisical as related to lax. And once they do that they change the pronunciation of lackadaisical to laxadaisical” said Anne Curzan, a professor of English at the University of Michigan.
Curzan says in surveys she’s done, half the people say lackadaisical and half say laxadaisical, but it doesn’t seem to be because of generation differences.
It’s seems that the combination of the letter K and S is what causes the confusion. Another mix-up can be found in words like especially and espresso.
“I would guess that what’s happening there is that the first syllable S in especially is not that common in English, and the first syllable X is very common in English. So some people are saying expecally or expresso,” said Curzan.
Sound swapping is what linguists would call metathesis. The letters S and K are two that are often swapped. One example is in the pronunciation of ask and ax.
“The pronunciation ax, as in ax a question, is a very stigmatized pronunciation in English. What most people don’t realize is that ax is older than ask. We have ax going all the way back to old English. And what seems to have happened is that ax became ask, and in fact Chaucer uses ax. Ax was a high form until at least the 16th century, and then it became seen as a non-standard form, and ask became the standard form,” Curzan said.
And finally, asterisk or astericks? You decide.