Although Lord of the Flies is essentially reported by school boys ranging in age from about 7 to 13 or 14 years old, it does have some interesting vocabulary.
Chapter 1 includes such words as "stupendous," "strident," "proffer"- (as in offer) and even "enmity." - (ill-will) These are not words the average high school student would otherwise be exopsed to.
The use of good vocabulary increases the book's usefulness and it would be a good idea to highlight any of these words as you read the novel for future use in essays about Lord of the Flies or any descriptive- style essay.
The words "intricacies" can be found about 13 pages in- page 23 in my version- Ralph and Piggy have just found the conch and are discussing it. Piggy then has the brilliant idea to use the shell to call the other boys and indicates that Ralph should try blowing it - "You try Ralph. You'll call the others."
Three short paragraphs later Ralph successfully blows the conch "and he trumpets a resounding blast" (MAXnotes on eNotes)
The paragraph in the text that includes the word "intricacies" describes it like this:
Ralph grasped the idea ... A deep, harsh note boomed under the palms, spread through the intricacies of the forest and echoed back....