임[연인] a lover(남자); a sweetheart(여자). ¶ 옛임 <俗> one's old flame. 임 그리운 마음 a heart pining for an absent love. 임을 그리워하다 miss one's love.As you can see, my dictionary defines 임 as "lover" or "sweetheart." However, something important is missing in the English definitions. A clue to what is missing can be found in the example phrases that follow the definitions (i.e. 임 그리운 마음; 임을 그리워하다).
In case you did not find the clue in the above sample phrases, here is the Korean definition:
사랑하고 그리워하는 사람, 또는 그러한 대상. ¶ ~ 생각. 그리운 ~.A translation of the Korean definition is "a person you love and long for." Notice the phrase, "long for"? That means 임 is referring to an " absent lover" or "absent sweetheart." Therefore, you cannot take your girlfriend to a friend's party and introduce her as your "임."
Actually, I do not think I have ever heard "임" used in conversation, but I have seen it in Korean poetry, which makes sense since people often write poems about "absent lovers." However, if you want to write about your absent lover, be careful not to make the same mistake some Koreas make by referring to him or her as "님."
Though 님 was once used a long, long time ago to mean "absent lover," 임 is used these days. Today, 님 is used as an honorific suffix with a meaning similar to "Mr." or "Mrs." or "Miss" or "Madam." It can also be attached to certain titles.