IPA: /ˈlʌvˌsɪk/
KK: /ˈlʌvˌsɪk/
Feeling very sad or unable to think clearly because of unrequited love or longing for someone.
After she left, he felt lovesick and couldn't focus on anything else.
Lovesick → It is formed from "love" (from Old English "lufu", meaning deep affection) and "sick" (from Old English "sēoc", meaning ill or unwell). The word "lovesick" describes the state of feeling unwell due to the emotional pain of love or longing for someone.
Think of feeling 'ill' ('sick') because of deep 'affection' ('love') — that's what lovesick means.