Character entity references can also have the format &name; where name is a case-sensitive alphanumeric string. For example, Î» can also be encoded as &lambda; in an HTML document. The character entity references &lt; , &gt; , &quot; and &amp; are predefined in HTML and SGML, because, ,  and & are already used to delimit markup. This notably does not include XML's &apos; (') entity.
Lack of facial expression. Lack of facial expression: Introduction. An absence of expression on the face is medically called flat affect. In many cases, the face mirrors the underlying emotions, and the person has limited emotions or various emotional or psychological disorders.
Facial droop is sagging of the face caused by loss of facial muscle tone. This is usually caused by an impairment of nerve function that supply the facial muscles, particularly involving the facial nerve. Most cases of facial droop are one-sided (unilateral) causing a distortion of the normal face structure.