If moral scepticism — the view that no moral beliefs are justified — is true, it presents a complex challenge for the meaning of ethical language. Moral scepticism could imply that although ethical language attempts to convey ideas about what is morally right or wrong, these ideas have no objective basis. However, even if scepticism is true, ethical language can still have meaning as it plays a role in influencing behaviour and expressing societal norms. It might be that the 'meaning' of ethical language, in this case, is not in its truth value but in its usage within human practices and its role in expressing and shaping our emotions, actions, and social interactions.

The emotive theory of ethics is a branch of non-cognitivism that focuses on the emotional aspects of moral language. It suggests that ethical statements are not about facts but are expressions of the speaker's emotions and are designed to evoke emotions in others. According to the emotive theory, when someone says "Charity is good," they are not making a statement about an objective fact of the world; rather, they are expressing a positive feeling towards charity and hoping to inspire a similar feeling in others. This theory contributes to non-cognitivism by providing a specific explanation for the nature of moral discourse, emphasising the expression and evocation of emotional responses rather than the assertion of empirical truths.

Error theory, associated with J.L. Mackie, is a meta-ethical view that, while maintaining that ethical statements are cognitive (thus they are capable of being true or false), claims that all such statements are false because they refer to intrinsic moral values that do not exist. According to error theory, when people use ethical language, they are systematically in error because they presuppose the existence of objective moral facts. For instance, saying "Stealing is wrong" assumes that there is a moral fact about the wrongness of stealing, but according to error theory, such a fact does not exist. Therefore, ethical language, while meaningful and structured to convey propositions, is fundamentally flawed because it fails to correspond to any objective moral reality.

Prescriptivism in ethical language, advocated by philosophers like R.M. Hare, suggests that moral statements not only express feelings but also function imperatively, prescribing actions. Unlike emotivism, which argues that moral language merely expresses emotions, prescriptivism maintains that ethical statements are universalisable prescriptions that guide behaviour. For instance, when someone says "Lying is wrong," according to prescriptivism, they're not just expressing disapproval of lying but also instructing against it and implying that if lying is wrong in one case, it is wrong in all similar cases. This approach recognises the action-guiding nature of moral language and attempts to provide a rational basis for ethical discussions and decisions, considering the consequences and consistency of our moral prescriptions.

The Frege-Geach problem poses a significant challenge to non-cognitivism by questioning how moral language can be coherent in complex sentences if it doesn’t express beliefs or propositions. Non-cognitivists argue that moral language merely expresses attitudes, not truths. However, when moral statements are embedded in conditional clauses or arguments, they seem to retain their meaning without directly expressing an attitude. For example, if one says, "If stealing is wrong, then encouraging stealing is wrong," the problem arises in explaining the moral terms' consistency without attributing to them a propositional quality. This indicates that moral language has a logical structure that non-cognitivism struggles to account for, suggesting that ethical expressions might indeed have truth-value or cognitive content.