butcher knife: a large sharp knife for cutting or trimming meat
knife: edge tool used as a cutting instrument; has a pointed blade with a sharp edge and a handle
gram's method: a staining technique used to classify bacteria; bacteria are stained with gentian violet and then treated with Gram's solution; after being decolorized with alcohol and treated with safranine and washed in water, those that retain the gentian violet are Gram-positive and those that do not retain it are Gram-negative