Animal they see, Noah seeing every second (5)
I believe the answer is:
hyena
'animal' is the definition.
(type of animal)
'they see noah seeing every second' is the wordplay.
'seeing every second' indicates alternate letters (I've seen 'every second of' mean this).
'they'+'see'+'noah'='theyseenoah'
The alternate letters of 'theyseenoah' are 'HYENA'.
(Other definitions for hyena that I've seen before include "Spotted scavenger" , "Dog-like scavenger" , "Carnivorous animal with howl like laughter" , "Carrion-eating, dog-like animal" , "Afr. doglike carnivore" .)