Document Type: Ischia Group Theory 2018
National University of Dnipro
University of State Fiscal Service of Ukraine
Department of Mathematics and Natural Sciences, College of Letters and Sciences, National University, USA
A subgroup $H$ of a group $G$ is called malonormal in $G$ if $H \cap H^x =\langle 1\rangle$ for every element $x \notin N_G(H)$. These subgroups are generalizations of malnormal subgroups. Every malnormal subgroup is malonormal, and every selfnormalizing malonormal subgroup is malnormal. Furthermore, every normal subgroup is malonormal. In this paper we obtain a description of finite and certain infinite groups, whose subgroups are malonormal.