To stop kissing or to cease an affectionate gesture of kissing.
From de- (to reverse) + osculate (from Latin osculari, meaning 'to kiss'). This is a rare, playful term formed by adding the reversal prefix to the verb 'osculate' to mean its opposite.
Deosculate is such a rare and whimsical word that most people have never heard it, even though 'osculate' (meaning 'to kiss') appears in crossword puzzles—it's a perfect example of how English theoretically lets you reverse almost any verb, but common sense prevents us from actually using most of these combinations.
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