Two flyers, the first transfixed by opening of Hobbes' Leviathan (8)
I believe the answer is:
behemoth
'leviathan' is the definition.
(I've seen this in another clue)
'two flyers the first transfixed by opening of hobbes'' is the wordplay.
'two flyers' means two replacements for 'flyer'.
'flyer' becomes 'moth' (something which flies).
'flyer' becomes 'bee' (I can't explain this - if you can you should give a lot more credence to this answer).
'the first' means one lot of letters go next to another.
'transfixed by' is an insertion indicator.
'opening of' says to take the initial letters.
The first letter of 'hobbes' is 'h'.
'moth' after 'bee' is 'beemoth'.
'beemoth' going around 'h' is 'BEHEMOTH'.
Can you help me to learn more?
(Other definitions for behemoth that I've seen before include "Big corporation" , "Something of impressive size or power" , "Monster" , "Huge organisation" , "Huge or monstrous person or thing" .)