The phrase "little vinegar" is often used metaphorically to describe a person who is somewhat grumpy, critical, or sour in their attitude or behavior. Full definition
A fresh tasting Red Habanero sauce with a solid kick and very little vinegar flavor. (heathotsauce.com)
Brooklyn's newest project space won't be drawing intrepid art lovers to far - off industrial areas like Red Hook, Bushwick, or Sunset Park, but to quaint little Vinegar Hill. (hyperallergic.com)
Mix the grated horseradish with a little vinegar and salt (some people like to add a bit of sugar, too), and store it in a jar in the refrigerator. (fieryfoodscentral.com)