Unsystematic Risk

Risk that affects a very small number of assets. Sometimes referred to as specific risk.

Investopedia Says:
For example, news that is specific to a small number of stocks, such as a sudden strike by the employees of a company you have shares in, is considered to be an unsystematic risk.

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One that is unique to a specific security. It is the antithesis of market (or systematic) risk. Thus, as portfolios become more diversified, the unsystematic risk moves to zero because the risks of specific securities cancel each other out. Components of unsystematic risk include economic risk, business risk, financial risk, and accounting risk. See also Beta.