As people age, it can be tricky to describe them without making them feel old. One way to avoid this is to use synonyms for the term "less young". Some options to consider include "middle-aged", "mature", "seasoned", "veteran", and "experienced". Each of these words carries a different connotation, so it's important to choose one that fits the individual you're describing. For instance, "mature" might be appropriate for someone in their 40s or 50s, while "veteran" might be better suited to someone who has been working in their field for many years. Whatever word you choose, be sure to use it thoughtfully and with respect for the person you're describing.