尚且 is a formal conjunction meaning 'even' or 'let alone', used to emphasize that if something is true for a lesser or more basic case, then it must certainly be true for a greater or more obvious one. The character 尚 means 'still, yet, or even' and conveys a sense of continuation or emphasis; 且 means 'moreover' or 'furthermore', adding a layer of logical progression. Together, they form a fixed two-character expression that signals contrastive escalation — often introducing the weaker element before moving to the stronger one in a rhetorical structure.

This word appears most frequently in written Chinese and formal speech, especially in argumentation, comparisons, or hypothetical reasoning. It typically precedes the subject or predicate of the subordinate clause and is almost always followed by a contrasting clause introduced by 更 (gèng) or 何况 (hékuàng). It carries a slightly literary tone and is rarely used in casual conversation.