Sorry, let me clarify. 勞工/worker legally means a person who works for an employer (what would otherwise in most cases be called a 受僱人/employee) under a 勞動契約/labor contract, which means under the Labor Standards Act. The definitions are in LSA Art. 2 Subpar. 2 and 6, but because the LSA doesn’t apply universally, the primary indicator of whether or not someone is a worker is actually whether or not the business entity falls within the scope of LSA Art. 3, the article that lists the applicable industries, and when it’s Art. 3 Par. 1 Subpar. 8 you need to scour the MOL’s website to find the list of everything in the “other” category, which includes buxibans. It annoyingly also includes private schools but not all private school teachers. 
An employee is usually a worker and vice-versa, but not always.
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