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 in this context is not related to a sagging facial skin, which may occur as a result of loss of elasticity of the skin. In these cases, a sagging face may be age-related, occur after a sudden loss of weight, debilitating illness or in cases of drug abuse, like a crystal meth addiction.