The definition of immoral is not following accepted principles of right and wrong behavior.
An example of immoral behavior is murder.
- not in conformity with accepted principles of right and wrong behavior, specif., depraved
- not in conformity with the accepted standards of proper sexual behavior, specif., unchaste or lewd
Origin of immoral; from in- + moral
Contrary to established moral principles.
(comparative more immoral, superlative most immoral)