/di lee"sheuhn/ , n.
1. an act or instance of deleting.
2. the state of being deleted.
3. a deleted word, passage, etc.
4. Genetics. a type of chromosomal aberration in which a segment of the chromosome is removed or lost.
[ 1580-90; deletion- (s. of deletio ) a destroying, equiv. to delet ( us ) (see DELETE) + -ion- -ION ]