Permuted Symbol Index (U)

            slot-unbound
                 unbound-slot
                 unbound-slot-instance
                 unbound-variable
                 undefined-function
  floating-point-underflow
                 unexport
                 unintern
                 union
with-compilation-unit
   internal-time-units-per-second
          decode-universal-time
          encode-universal-time
             get-universal-time
                 unless
                 unread-char
           print-unreadable-object
                 unsigned-byte
                 untrace
                 unuse-package
                 unwind-protect
            char-upcase
         nstring-upcase
          string-upcase
                 update-instance-for-different-class
                 update-instance-for-redefined-class
                 upgraded-array-element-type
                 upgraded-complex-part-type
                 upper-case-p
         package-use-list
                 use-package
                 use-value
         package-used-by-list
                 user-homedir-pathname