Def.- A cutting, often ironic remark intended to wound.
Syn.- satirical, snide, catty, mocking, sardonic
"Hitler is a fiend for films, and on evenings when no important conferences are on or he is not overrunning a country, he spends a couple of hours seeing the latest movies in his private cinema room at the Chancellery.
-"Hitler's Workday" by WIlliam Shirer
The tone of this passage is sarcastic. This is evident by the author's phrase, " ....When no important conferences are on or he is not overrunning a countr.y" Here the author acts as jif dictating a country is a casual job for Hitler to be doing, invoking a sense of sarcasm amongst the readers, and also expresses Shirer's distaste for Hitler.