- a volatile liquid, as turpentine, used to dilute paint, varnish, rubber cement, etc., to the desired or proper consistency.
- a person who adds thinners to paints, varnishes, etc.
- a person who specializes in weeding plants, pruning shrubbery, thinning fruit, etc.
- comparative of thin.
- a solvent, such as turpentine, added to paint or varnish to dilute it, reduce its opacity or viscosity, or increase its penetration into the ground
