web vs spider web

web and spider web both are nouns.

Word	Noun	Adjective	Verb	Adverb
web	Yes	No	Yes	No
spider web	Yes	No	No	No

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

Other hyponyms of web include spider's web.

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

web: an intricate network suggesting something that was formed by weaving or interweaving
spider web: a web spun by spiders to trap insect prey

Other hyponyms of web include spider's web, tent, webbing.

web (noun)	spider web (noun)
the flattened weblike part of a feather consisting of a series of barbs on either side of the shaft	a web spun by spiders to trap insect prey
membrane connecting the toes of some aquatic birds and mammals	a web resembling the webs spun by spiders
an intricate trap that entangles or ensnares its victim
a fabric (especially a fabric in the process of being woven)
computer network consisting of a collection of internet sites that offer text and graphics and sound and animation resources through the hypertext transfer protocol
an interconnected system of things or people
an intricate network suggesting something that was formed by weaving or interweaving

web (verb)	spider web (verb)
construct or form a web, as if by weaving