Case-hardened and Fiddle with

Case-hardened adjective - Having or showing a lack of sympathy or tender feelings.

Fiddle with and case-hardened are semantically related. In some cases you can use "Fiddle with" instead a verb phrase "Case-hardened".

Fiddle with verb - To handle thoughtlessly, ignorantly, or mischievously.

Case-hardened and fiddle with are semantically related. Sometimes you can use "Case-hardened" instead a verb "Fiddle with".