concetration
when a large amount of solute is added to the solvent. Eventually it will reach a point where no more solute will dissolve
dilute
adding more solvent to a concentrated solution will dilute it. A dilute solution only has a small amount of solute in it
saturation
When too much solute has been added to the solvent and it will no longer dissolve (the extra solute settles at the bottom of the solution)