Insensitive (7)
'insensitive' is the definition.
(similar in meaning)
This is all the clue.
(Other definitions for callous that I've seen before include "Cruel or unsympathetic" , "Emotionally hardened" , "Not feeling" , "Hard and unfeeling" , "Insensitive, cruel" .)
'insensitive' is the definition.
(synonyms)
This is the entire clue.
(Other definitions for numb that I've seen before include "Unable to move" , "Insensate" , "Without feeling" , "Deaden" , "Stunned, insensible" .)
'insensitive' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for tactless that I've seen before include "Indiscreet" , "Without subtlety or sensitivity" , "Maladroit" , "Unlikely to make Diplomatic Service" , "Let's cast away, lacking sensitivity" .)
'insensitive' is the definition.
(a crass comment might be insensitive)
This is the entire clue.
(Other definitions for crass that I've seen before include "'Gross, vulgar (5)'" , "Tactless, boorish" , "Asinine" , "Boorish about scars" , "Coarse" .)