Still. Any apparatus capable of being used for separating alcoholic or spirituous vapors, or spiritous solutions, or spirits, from spirituous solutions or mixtures, but shall not include stills used for laboratory purposes or stills used for distilling water or other nonalcoholic materials where the cubic distilling capacity is one gallon or less.
27 CFR § 29.45
When used in this subpart and in the forms prescribed under this subpart, where not otherwise distinctly expressed or manifestly incompatible with the intent thereof, terms shall have the meaning ascribed in this section. Words in the plural form shall include the singular, and vice versa, and words in the masculine shall include the feminine. The terms includes and including do not exclude things not enumerated which are in the same general class.