lock ‧ et /ˈlɒkət, ˈlɒkɪt $ ˈlɑː-/ BrE AmE noun [countable]
[ Date: 1300-1400 ; Language: Old French ; Origin: locquet , from Middle Dutch loke 'latch' ]
a piece of jewellery that you wear around your neck on a chain, with a small metal case in which you can put a picture, a piece of hair etc