The phrase "knockout model" refers to a person who is exceptionally attractive or stunning in appearance. It suggests that this individual's attractiveness is so impactful that it can "knock out" or impress others. Full definition
Evidence from mouse knockout models and human mendelian disorders suggest that these transcription factors have a function in determining cell identify in the developing breast. (vicc.org)
Construction of somatic cellular knockout models for the determination of protein functional impacts on various cellular processes: (mdanderson.ilabsolutions.com)
For example, we often screen only 15 - 25 mice when generating knockout models with CRISPR and find that many, if not all, the mice carry a frameshift mutation. (blog.addgene.org)