Description Identifies a horizontal span of columns and associated attributes that can subsequently be referenced by its spanname to provide attributes repeatedly used in the entries or entry tables in several rows of the table group controlled by the group <colsdef>, or within the specific <thead>, <tfoot>, or <tbody> context in which the <spanspec> occurs. <Namest> and <nameend> identify the first and last columns in increasing order that identify the span. The reason <colname> is used rather than <colnum> in identifying <spanspec> is that the names are independant of revisions that may change the number of inserted/deleted columns, as long as namest remains to the left of (has a smaller colnum than) <nameend>. <spanspec>s set on <thead> or <tfoot> override those on the containing <tgroup> and apply to just the <thead> or<tfoot>. <spanspec>s from the containing <tgroup> apply to <tbody>.