"Baloney!” (5)
'baloney' is the definition.
(thesaurus)
This is all the clue.
(Other definitions for eyewash that I've seen before include "Visual cleansing agent - nonsense" , "Balderdash" , "Insincere talk or optical lotion" , "Slangy nonsense or optical cleanser" , "this is soothing sight" .)
(Other definitions for pshaw that I've seen before include "Voice impatience" , "Contemptuous riposte" , "it's disgusting" , "Contemptuous cry" , "Expression of impatience" .)