akin, apropos, germane, proper, appropriate, essential, pertinent, relevant.
Such a purpose was alien _to_ (or _from_) my thought: _to_ preferable.
A naturalized citizen is not an _alien_, though a _foreigner_ by birth, and perhaps a _stranger_ in the place where he resides. A person of foreign birth not naturalized is an _alien_, though he may have been resident in the country a large part of a lifetime, and ceased to be a _stranger_ to its people or institutions. He is an _alien_ in one country if his allegiance is to another. The people of any country still residing in their own land are, strictly speaking, _foreigners_ to the people of all other countries, rather than _aliens_; but _alien_ and _foreigner_ are often used synonymously.
citizen, fellow-countryman, native-born inhabitant, countryman, native, naturalized person.
Aliens _to_ (more rarely _from_) our nation and laws; aliens _in_ our land, _among_ our people.
akin, equivalent, kindred, same, analogous, homogeneous, like, similar, equal, identical, resembling, uniform.
_Alike_ is a comprehensive word, signifying as applied to two or more objects that some or all qualities of one are the same as those of the other or others; by modifiers _alike_ may be made to express more or less resemblance; as, these houses are somewhat (_i. e._, partially) _alike_; or, these houses are exactly (_i. e._, in all respects) _alike_. Cotton and wool are _alike_ in this, that they can both be woven into cloth. Substances are _homogeneous_ which are made up of elements of the _same_ kind, or which are the _same_ in structure. Two pieces of iron may be _homogeneous_ in material, while not _alike_ in size or shape. In geometry, two triangles are _equal_ when they can be laid over one another, and fit, line for line and angle for angle; they are _equivalent_ when they simply contain the same amount of space. An _identical_ proposition is one that says the same thing precisely in subject and predicate. _Similar_ refers to close resemblance, which yet leaves room for question or denial of complete likeness or identity. To say "this is the _identical_ man," is to say not merely that he is _similar_ to the one I have in mind, but that he is the very _same_ person. Things are _analogous_ when they are _similar_ in idea, plan, use, or character, tho perhaps quite unlike in appearance; as, the gills of fishes are said to be _analogous_ to the lungs in terrestrial animals.