Phubbing refers to the activity of being impolite in a social situation by looking at your phone instead of paying attention to the person you are with.
Have you ever been chatting to a friend and succumbed to the temptation, mid-conversation, of checking your mobile and apologetically interrupting the flow because you just can't resist replying to a text message? If so, then you're guilty of a 21st century impropriety now known as phubbing. People who can’t help checking their phones during a conversation are known as phubbers.
The word phubbing and its related derivations first appeared in 2012, formed from a blend of the noun phone and verb snub meaning 'to insult someone by ignoring them'.
Opinion polls indicate that a one-to-one conversation is the most frustrating situation in which to be phubbed, causing the victim to feel as if the other person is disinterested in them or the conversation in general. Travelling with someone in a car or on public transport, however, is deemed to be the most 'acceptable' situation in which phubbing could take place. (Source: macmillandictionary.com)