We can say, "Those pepperoncinis are hot" or "That woman is hot" or "It's was hot in Phoenix today" or "Donald Trump's candidacy is a hot topic" - these all contain the word "hot" - which although are all spelled the same and pronounced the same - have wholly different meanings. Any young teen could discern these various homonyms because of the context their respective sentences give them. Body language signals also very often have multiple meanings - depending on the other nonverbal signs with which they are clustered. Lip biting is but one example of this nonverbal phenomenon.
In this image we see Ana Ivanovic, currently 7th in WTA women's singles rankings. Today - the first day of the U.S. Open Tennis Championship, this Serbian was upset by Slovakia's Dominika Cibulkova (6-3, 3-6, 6-3). Note in this image Ms. Ivanovic is biting her bottom lip. In this context it's indicative of some anxiety (although not excessive) as well as very concentrated, focused thought. Intriguingly, within the realm of tennis, lip biting is almost never seen during a serve - essentially only during a return.
As with the "hot" homonym exampled above (and in a non-tennis setting) when Lip Biting is accompanied by a different set of facial and body expressions - it can be indicative of varied meanings such as - anger, anxiety, focused thought, sadness, embarrassment, mischievousness, frustration, vulnerability and even sexual arousal. Yet without knowing and recognizing all the words in a nonverbal sentence, most people often have no idea how to color the emotional nuance of the moment.
Here Heather Watson (Great Britain) is returning to Lauren Davis (United States). Watson lost to the match, 7-6, 7-6.
Canadian Milos Raonic - in another lip-biting return defeated Tim Smyczek (U.S.), 6-4, 7-6 (8), 6-1.
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