Indignation is anger at something you believe is unjust. Not simple temper — offence taken on principle.
The sense of unfairness is essential, and it is what makes indignation feel righteous to the person having it. It takes at. The standard phrase is righteous indignation, which is nearly always used with a raised eyebrow, since the writer usually thinks the outrage is being enjoyed. Newspapers manufacture it for a living. The adjective indignant describes the person, and an indignity is the humiliation that causes it.
1nounindignationAnger at treatment felt to be unjust.
“There was general indignation at the decision.”
Indignation is the sense that a thing is unworthy. Latin indignus is in, not, plus dignus, worthy, so indignation is anger at what does not deserve to have happened.
Latin
indignātiō
Old French
indignation
Middle English
indignacioun
English, today
indignation
Built from
From Middle English indignacioun, borrowed from Old French indignation, from Latin indignātiō, from indignor (“to scorn, resent”), from indignus (“unworthy, not fitting”), from in- (“not”) + dignus (“worthy, appropriate”). Attested since ca. 1374. a doublet of indignatio.
Etymology from Wiktionary, CC BY-SA