What does lapsidasical mean?

"Lapsidasical" is not a recognized word in the English language. It seems like a possible misspelling or a made-up word.

Perhaps you meant "lackadaisical"?

Lackadaisical means:

* Showing a lack of enthusiasm and effort; careless and lazy.

* Indifferent; listless; lethargic.

For example: "The students were lackadaisical in their approach to the assignment, resulting in poor grades."