Spirituality gets many definitions .
The proper definition of spirituality is getting fulfilment from faith in the supernatural and or embracing obligations that come from the spiritual realm.
It is not true that religion and spirituality can be separated. People who agree with the thought that they can say that you can’t have religion without spirituality but you can have spirituality without religion. Actually the two go together. A spiritual person who denies that he or she is religious is actually his own individualistic religion.
A religion with only one member is still a religion.
Faiths that do not believe in a supernatural soul such as the Christadelphians still urge people to be spiritual . Some atheists say atheism is spiritual for it gives you meaning in life and can be fulfilling. But then what do they need the word spiritual for? Why not just use the word fulfilling? For example, we might say that a person has done something in an unselfish spirit. This is a metaphor. We only mean that their attitude is unselfish. And there need be no spirit involved in that!
An atheist should never speak of spiritual.