Racism - the belief that different races possess distinct characteristics, abilities, or qualities, especially so as to distinguish them as inferior or superior to one another (Oxford Dictionary).
It was once believed there were 3 races, Caucasoid, Mongoloids (including Chinese, Japanese, Koreans, and American Indians, etc.), and Negroid. Khoisanoids or Capoids (Bushmen and Hottentots) and Pacific races (Australian aborigines, Polynesians, Melanesians, and Indonesians) may also be distinguished.
In the past, Caucasoid human societies believed and propagated the belief Caucasoid persons were superior to non-Caucasoid persons. Asking biologists, "race" is synonymous with "subspecies". There are no subspecies in the species Homo Sapiens. Scientifically it is impossible for humans to be racist against. Homo Sapiens could be racist against Neanderthal, and vice versa.
Is there prejudice and bigotry among humans based on ethnicity, gender, sexual orientation, national origin, religion, etc.? Yes. Is it systemic in the United States? I guess it depends on what system is being referred to.
By statutory law in the United States government and its agents are prohibited from discriminating against persons do to the person's ethnicity, gender, age, sexual orientation, national origin, or religion. By design there is no systemic prejudice in the United States government. If agents of the government discriminate (i.e. act on prejudices as listed) the are in violation of law and should be sanctioned.
Is there socio-economic disparities seen which effect ethnic minorities in the United States at a higher per capita percentage? Yes.