The term 'valued highly' can be expressed in a variety of ways, such as PRIZED (6 letters), TREASURED (9 letters), DEAR (4 letters), and ESTEEMED (8 letters). PRIZED implies that something is of great worth or value, while TREASURED suggests that it is held in high regard and is cherished. DEAR implies that the item is beloved and has a special place in one's heart, while ESTEEMED implies that it is respected and admired. All of these words indicate that the item is highly valued.