Weighs down shelters round Noah's vessel (7)
I believe the answer is:
darkens
'weighs down' is the definition.
Although both the answer and definition are verbs in their -s form, I can't understand how one could define the other.
'shelters round noah's vessel' is the wordplay.
'shelters' becomes 'dens' (I've seen this in another clue).
'round' indicates putting letters inside.
'noah's vessel' becomes 'ark' (Noah's ark).
'dens' going around 'ark' is 'DARKENS'.
Can you help me to learn more?
(Other definitions for darkens that I've seen before include "Gets black" , "becomes gloomy" .)