As nouns the difference between gremlin and dwarf
is that gremlin
is a mythical creature reputed to be mechanically and mischievously inclined to damage or dismantle machinery while dwarf
is (mythology) any member of a race of beings from (especially scandinavian and other germanic) folklore, usually depicted as having some sort of supernatural powers and being skilled in crafting and metalworking, often depicted as short, and sometimes depicted as clashing with elves.
As an adjective dwarf is
As a verb dwarf is
to render (much) smaller, turn into a dwarf (version).