The word is used constantly and means noticeably different things to different speakers.
Earlier religious usage
A term describing the inner life within a religious tradition.
Which assumed the tradition rather than replacing it.
The modern separation
Spiritual but not religious as a self-description.
Which surveys have tracked growing across several countries.
What people mean by it
Meaning, connection, transcendence and practice, in varying mixtures.
Critiques
Concerns about vagueness and about detachment from community.
Which come from religious and secular directions alike.
Why the meaning shifted
Declining institutional religious affiliation alongside continued interest in meaning and practice.
Which left a vocabulary gap that this word filled.
Survey data across several countries shows the pattern clearly: attendance falling faster than belief, and belief falling faster than interest in practice.
What it is used to mean
Anything from formal contemplative practice to a general sense of wonder.
Which makes the word almost useless without further specification.
Religious critiques
Concerns about practice detached from community and accountability.
Secular critiques
Concerns about vagueness and commercial exploitation.
A more useful approach
Saying specifically what practice or belief is meant.
What survey data actually shows
Institutional affiliation and attendance declining in many countries while reported belief and interest in practice decline more slowly.
Which produces a large group who describe themselves in terms that did not previously exist as a category.
The pattern varies enormously by country, and generalisations drawn from any one society travel badly.
Practice without belief
People attending, meditating or observing festivals without holding the associated beliefs.
Which is common and long predates the current vocabulary.
Commercial spirituality
A substantial market in courses, retreats and products.
Which attracts criticism from several directions.
Being specific
Naming the actual practice rather than the category.
A general note
This is description rather than argument for any position.
Why definitional vagueness matters
When a word covers formal contemplative practice, holding a general sense of meaning, buying a course, and not attending a church, it stops carrying information.
Which makes research using it difficult and public conversation about it frustrating.
Being specific about what practice, belief or affiliation is meant costs nothing and clarifies a great deal.
Historical usage
The term used within religious traditions to describe their own inner disciplines.
Which is a narrower and clearer sense.
Research on wellbeing
Findings that depend heavily on how the term is operationalised.
Which limits what can be concluded.
The market
Books, apps, retreats and courses.
Which is a substantial industry.
A general note
This is descriptive and takes no position on any belief.
How this article treats its subject
Everything here is written descriptively. Where a practice belongs to a living religious tradition, the aim is to say accurately what that tradition does and says about it, without arguing for or against its beliefs. Those are questions for the traditions themselves and for the people who belong to them.
Where research is mentioned, the intention is to report what studies have found rather than what enthusiasts or critics have claimed about them, including where the findings are weaker or more contested than popular coverage suggests.
A note on why the history matters
A great deal of contemporary spiritual and wellbeing material presents itself as ancient when it is recent, or as universal when it belongs to a particular tradition and place. Neither of those is necessarily dishonest, and both make it harder to understand what one is actually doing.
Knowing where a practice comes from, who developed it, what it was originally for and what changed along the way does not diminish it. It usually makes it more interesting, and it makes claims about it easier to evaluate.
Where to read further
Primary texts in good annotated translations, academic histories, and practitioners speaking about their own tradition are all more reliable than secondary summaries, including this one. Most of the traditions discussed here have extensive scholarly literature accessible to general readers, and university presses publish short introductory volumes on nearly all of them.
Where a practice has physical or psychological effects, medical and mental health professionals are the appropriate source of guidance, and nothing here is intended as advice of that kind.
On sources and disagreement
Scholars disagree about much of this material, sometimes sharply, and where that is the case it has been noted rather than resolved. Presenting contested questions as settled would be more comfortable to read and less accurate.
That applies particularly to questions of origin and influence, where the evidence is frequently thin and the temptation to fill gaps with a tidy narrative is strong. Where something is genuinely uncertain, the honest description is that we do not know.
A final word on approach
Traditions described here belong to living communities of people who practise them seriously. Writing about them from outside carries an obligation to get the details right and to avoid claiming more familiarity than the writing supports.
Where this article is thin, the traditions own sources are the correction.