By oneself, solitary.
Lacking peers who share one's beliefs, experiences, practices, etc.
Not requiring anything further; merely.
By oneself; apart from, or exclusive of, others; solo.
Without outside help.
Used to emphasize the size or extent of something by selecting a subset.
Not permitting anything further; exclusively.
Alone in a category.
Singularly superior; the best.
Without sibling; without a sibling of the same gender.
As recently as.
Without others or anything further; exclusively.
Used to express surprise or consternation at an action.
Introduces a disappointing or surprising outcome that renders futile something previously mentioned.
No more than; just.
Under the condition that; but.
But; except.
An only child.