Intolerance is an unwillingness to accept difference. Religious intolerance, stamp out intolerance, intolerance of dissent.
The medical sense is quite separate and not a moral one: lactose intolerance means the body cannot process something, and it differs from an allergy in that the immune system is not involved. The prefix in- simply reverses tolerance.
1nounintoleranceAn unwillingness to accept difference.
“The school teaches children that intolerance of other religions has no place in the classroom.”
intolerance is an attitude.
Latin intolerantia comes from in-, not, plus tolerare, to bear or endure.
French
intolérance
English, today
intolerance
French intolérance, itself from in- + tolérance or borrowed from Latin intolerantia (“insolence, insufferableness; (very rare) intolerance”). by surface analysis, in- + tolerance.
Etymology from Wiktionary, CC BY-SA