godan verb (-u), intransitive verb
lean against each other
Describes two or more people or things physically leaning on one another for support.
疲れた二人はソファでもたれ合っていた。
The exhausted pair were leaning against each other on the sofa.
godan verb (-u), intransitive verb
rely on each other; depend on each other; scratch each other's backs
Metaphorical use for a mutual, often unhealthy, dependence where each party leans on the other to avoid individual responsibility.
あの部署はみんなでもたれ合って、誰も責任を取ろうとしない。
In that department, everyone relies on each other and no one tries to take responsibility.