Allusion is an indirect
or passing reference to some event, person, place, or artistic work, the nature
and relevance of which is not explained by the writer but relies on the
reader's familiarity with what is thus mentioned. The technique of allusion is an
economical means of calling upon the history or the literary tradition that
author and reader are assumed to share, although some poets (notably Ezra Pound
and T. S. Eliot) allude to areas of quite specialized knowledge.