Aspiration, n.
Etymology: [L. aspiratio, fr. aspirare: cf. F. aspiration.]
1. The act of aspirating; the pronunciation of a letter with a full or strong emission of breath; an aspirated sound. If aspiration be defined to be an impetus of breathing. Wilkins.
2. The act of breathing; a breath; an inspiration.
3. The act of aspiring of a ardently desiring; strong wish; high desire. "Aspirations after virtue." Johnson. Vague aspiration after military renown. Prescott.
Shades of meaning
Fernald has no entry of its own for aspiration; he lists it under aim, ambition, desire.
Where he writes about it:
Aspiration, design, endeavor, purpose, referring to the mental acts by which the aim is attained, are often used as interchangeable with aim. — from aim
Aspiration applies to what are viewed as noble aims; endeavor, design, intention, purpose, indifferently to the best or worst. — from aim
Aspiration has less of decision than the other terms; one may aspire to an object, and yet lack the fixedness of purpose by which alone it can be attained. — from aim
Aspiration is the desire for excellence, pure and simple. — from ambition
The prizes of aspiration are virtue, nobility, skill, or other high qualities. — from ambition
But, at the highest, emulation is inferior as a motive to aspiration, which seeks the high quality or character for its own sake, not with reference to another. — from ambition