The term 'Level of Achievement' can be defined as the height or degree of success that has been attained. This can be measured in terms of a person's accomplishments, skills, or reputation. Two crossword solutions for this term are 'PLATEAU' and 'STATURE'. A PLATEAU is a period of stability or stagnation in which progress is halted or slowed. STATURE is a measure of one's importance or standing in society. Both of these words can be used to describe the level of achievement that someone has reached.