Like a U on its right side with a line under it. For sets x and y, x subseteq y if all elements of x are also elements of y. (1995-02-03)

In addition suitable contents:
[ 2 ] [ al ] [ an ] [ ar ] [ b ] [ bs ] [ de ] [ element ] [ er ] [ et ] [ gh ] [ h ] [ ht ] [ id ] [ in ] [ it ] [ ke ] [ li ] [ line ] [ ls ] [ ne ] [ re ] [ se ] [ set ] [ si ] [ so ] [ su ] [ th ]