anti-aliasing
noun
an·ti-ali·as·ing 
ˌan-tē-ˈā-lē-ə-siŋ,
-ˈāl-yə-,
ˌan-ˌtī- variants or antialiasing
: a procedure used in digital graphics processing for smoothing lines and removing visual distortions
Word History
Etymology
anti- + alias entry 2 (in sense "spurious frequency generated during digital processing of an image") + -ing entry 1
First Known Use
1978, in the meaning defined above