A passive speaker (also referred to as a receptive bilingual or passive bilingual) is a category of speaker who has had enough exposure to a language in childhood to have a native-like comprehension of it, but has little or no active command of it.
For example, around 10% of the Ainu people who speak the language are considered passive speakers.
They are also found in areas where people grow up hearing another language outside their family with no formal education.
François Grosjean argues that there has been a monolingual bias regarding who is considered a 'bilingual' in which people who do not have equal competence in all their languages are judged as not speaking properly.
[4] That means that speakers may not admit to their fluency in their passive language although there are social (extralinguistic) factors that underlie their different competencies.