The word "oronym" was coined by Gyles Brandreth in The Joy of Lex, William Morrow, New York, 1980.
It refers to phrases or sentences whose sound can be interpreted in more than one way as another valid phrase or sentence.

A simple example would be the sentences:
The sons raise meat.
The sun's rays meet.

Oronyms do not need to respect word boundries. In fact, oronyms can rely on the pronounciation and even coarticulation of the sounds of the words.

The sentences:
peace talks
pea stalks
are a good example of oronyms where word boundries do not align.

Mistakenly hearing an oronym in a song or poem instead of the actual text is refered to as a mondegreen.

The French holorime1 is a word game based on coupled oronyms.

1. Thanks to jaubertmoniker