the whole nine yards

Meanings

Adverb

• All the way; with everything done completely or thoroughly.

Noun

• (And) everything;

Origin

• Dave Wilton summarises the findings of Bonnie Taylor-Blake and others:
• :The phrase doesn’t have one particular origin, nor does it represent one particular metaphor. Instead, it seems to have evolved from a sense of yard meaning a vague quantity of something. Later, the words full or whole were attached to it, and even later it was quantified by the numbers six and nine, with the whole nine yards eventually winning out and becoming the canonical form. Use of the full phrase was for a long time restricted to the American Midwest, in particular to the region around the Kentucky-Indiana border, before breaking out into general American parlance in the middle of the twentieth century. [...]
• :So regardless of what someone else has told you, the whole nine yards does not refer to the length of a belt of WWII machine-gun ammunition, the amount of material needed to make a Scottish kilt, the number of spars on a sailing ship, the amount of concrete a cement mixer holds, or anything else.