millstone

English Thesaurus

1. one of a pair of heavy flat disk-shaped stones that are rotated against one another to grind the grain (noun.artifact)

hypernym	:	stone,
definition	:	building material consisting of a piece of rock hewn in a definite shape for a special purpose (noun.artifact)

part meronym	:	gristmill,
definition	:	a mill for grinding grain (especially the customer's own grain) (noun.artifact)

2. any load that is difficult to carry (noun.artifact)

hypernym	:	burden, load, loading,
definition	:	weight to be borne or conveyed (noun.artifact)

3. (figurative) something that hinders or handicaps (noun.cognition)

hypernym	:	balk, baulk, check, deterrent, handicap, hinderance, hindrance, impediment,
definition	:	something immaterial that interferes with or delays action or progress (noun.cognition)