harmonious
adj.describing things that go together perfectly or people who get along without fighting.
adj.characterised by agreement in feeling, action, or sound; forming a pleasing or consistent whole. Often used to describe social relationships or aesthetic arrangements.
“The team worked in a harmonious way to finish the project.”
“The interior designer chose a harmonious color palette of soft blues and greens to create a relaxing bedroom.”
“The treaty aimed to establish a more harmonious relationship between the neighboring nations after decades of border disputes and economic competition.”
Typically follows a linking verb like 'be' or 'become', or precedes the noun it modifies.
“Insisting on politeness, moderation and reasonableness may make political debate more harmonious among those already fully included.”
From Middle French harmonieux; by surface analysis, harmony + -ous.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.