The term 'pervading tone' is used to describe the overall MOOD or TENOR of a situation. It is the feeling that is created by the combination of all the elements present in a given environment. The crossword solutions for this term are 'MOOD' (4 letters) and 'TENOR' (5 letters). MOOD refers to the atmosphere or emotional quality of a situation, while TENOR is the underlying attitude or sentiment that is conveyed. Together, these two words create the pervading tone of a situation.