bootlace worm
n (Animals) a nemertean worm, Linens longissimus, that inhabits shingly shores and attains lengths of over 6 m (20 ft)
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014