loading vs overload

loading and overload both are nouns.

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

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

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

loading (noun)	overload (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	an electrical load that exceeds the available electrical power
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)	overload (verb)
	fill to excess so that function is impaired
	place too much a load on
	become overloaded