/ hɑːˈməʊniəs; NAmE hɑːrˈmoʊ-/ adjective
1.
( of relationships, etc. ) friendly, peaceful and without any disagreement
2.
arranged together in a pleasing way so that each part goes well with the others
SYN pleasing :
a harmonious combination of colours
3.
( of sounds ) very pleasant when played or sung together
► har·mo·ni·ous·ly adverb :
They worked very harmoniously together.