loading vs overburden

loading and overburden both are nouns.

Word	Noun	Adjective	Verb	Adverb
loading	Yes	No	No	No
overburden	Yes	No	Yes	No

As nouns, overburden is a hyponym of loading; that is, overburden is a word with a more specific, narrower meaning than loading:

Other hyponyms of loading include burthen, dead load, live load, superload, millstone, overload, overload.

loading (noun)	overburden (noun)
the labor of putting a load of something on or in a vehicle or ship or container etc.	an excessive burden
goods carried by a large vehicle	the surface soil that must be moved away to get at coal seams and mineral deposits
weight to be borne or conveyed
a quantity that can be processed or transported at one time
the ratio of the gross weight of an airplane to some factor determining its lift

loading (verb)	overburden (verb)
	burden with too much work or responsibility
	load with excessive weight