Lay odds of trek maps being seen before test (8)
I believe the answer is:
temporal
'lay' is the definition.
(both can mean earthly as opposed to spiritual)
'odds of trek maps being seen before test' is the wordplay.
'odds of' means one should take alternating letters (the letters in odd-numbered positions are used).
'being seen before' means one lot of letters go next to another.
'test' becomes 'oral' (oral is a type of examination).
'trek'+'maps'='trekmaps'
The alternate letters of 'trekmaps' are 'temp'.
'temp'+'oral'='TEMPORAL'
(Other definitions for temporal that I've seen before include "Worldly, secular" , "Secular; of the temples" , "profane" , "Of wordly affairs, not spiritual" , "about the side of the head" .)