engagement ring

Translations
обручальное кольцо
He gave her an engagement ring.
Он подарил ей обручальное кольцо.
Definitions
An engagement ring is a ring given to signify that the wearer has agreed to marry the person who gave the ring, typically featuring a prominent gemstone, often a diamond, and is traditionally worn on the fourth finger of the left hand.
Words
engagement

adjective
помолвочный
ring

noun
кольцо