A secret (method or device or formula) that gives a manufacturer an advantage over the competition WordNet 3.0 & Open English WordNet

A trade secret is an intellectual property that has inherent economic value because it is not generally known or readily ascertainable by others, and which the owner takes reasonable measures to keep secret. Wikipedia

Formula, practice, process, design, instrument, pattern, or compilation of information which is not generally known or reasonably ascertainable, by which a business can obtain an economic advantage over competitors or customers. Wikipedia Disambiguation

Business information kept secret to gain or maintain a competitive advantage Wikidata

A formula, practice, process, design, instrument, pattern, or compilation of information used by a business to obtain an advantage over competitors within the same industry or profession, which kept secret from those competitors or the public. Wiktionary

Formula, practice, process, design. Wiktionary (translation)