In medicine, a tincture is an alcoholic extract (e.g. of leaves or other plant material) or solution of a non-volatile substance; e.g. of iodine, mercurochrome). To qualify as a tincture, the alcoholic extract is to have a ethanol percentage of at least 40-60% (sometimes a 90% percent pure liquid is even achieved). Solutions of volatile substances were called spirits, although that name was also given to several other materials obtained by distillation, even when they did not include alcohol.
To make a more precise tincture^, more extensive measuring can be done by combining 1 part herbs with a water-ethanol mixture of 2-10 parts, depending on the herb itself. With most tinctures, however, 1 part water at 5 parts ethanol is used.
Examples of spirits include: