flirt (flʉrt)

Definition

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to pay amorous attention to someone without serious intentions or emotional commitment; play at love
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Flirting is much more than just a bit of fun: it is a universal and essential aspect of human interaction and is to be found in all cultures and societies around the world. Flirting is a basic instinct, part of human nature: Human achievements in everything from art to rocket science may be merely a side-effect of the essential ability to charm.

Like every other human activity, flirting is governed by a complex set of unwritten laws of etiquette.
These rules dictate where, when, with whom and in what manner we flirt. We generally obey these unofficial laws instinctively, without being conscious of doing so. We only become aware of the rules when someone commits a breach of this etiquette – by flirting with the wrong person, perhaps, or at an inappropriate time or place.

Men find it particularly difficult to interpret the more subtle cues in women's body-language, and tend to mistake friendliness for sexual interest. Hence, women tend to use and abuse of this flirtagious window of uncertainty.