Crew welcoming positive response, in a sense (8)
I believe the answer is:
eyesight
'a sense' is the definition.
(eyesight is a kind of sense)
'crew welcoming positive response' is the wordplay.
'crew' becomes 'eight' (I've seen this before).
'welcoming' indicates putting letters inside (in sense of 'inviting in').
'positive response' becomes 'yes' (I've seen this before).
'eight' enclosing 'yes' is 'EYESIGHT'.
'in' acts as a link.
(Other definitions for eyesight that I've seen before include "quality of viewing" , "Ability to see" , "Perceptive faculty" , "Requirement to look" , "Power of vision" .)