The following is a definition of dilution(posted 8474 days ago)"Dilution : The effect of changing the concentration of a solution by the addition of more solvent. A dilution of 1:10 means the addition of 9 volumes of the solvent to 1 volume of the original solution. The resulting solution is one tenth as concentrated as the original."
Taken from:
http://www.nico2000.net/DataSheets/glossary.html