Here is a paragraph from The Running Hare: The Secret Life of Farmland (2016) by John Lewis-Stempel.
Quite aside from the de-naturing of contemporary childhood, more about collecting apps for Apple iPhones than scrumping apples, there was always the terrible destructivity of butterfly collecting. Due to the collectors the ineffability of evolution is better understood; minute wing variation in the pretty marsh fritillary, discovered Professor E. B. Ford, was no accident but a real, living adjustment to environment. Neither can the collectors be blamed for the butterflies we have lost, in the Lady Bracknell understanding of the word, such as the English large copper, the chequered skipper, the English large blue . . . Pollution, agribusiness, infrastructural development are the true butterfly-killers.
What does "in the Lady Bracknell understanding of the word" mean here? What does "the word" refer to?
I assume that Lady Bracknell is the character from The Importance of Being Earnest. I read the play, but still could not get a clue.