-age

The suffix -age can form nouns that have a collective meaning of what is denoted by the first element. Some common examples are leafage (or foliage), baggage, signage, wordage, plumage, etc.

leafage, foliage

Leafage means leaves collectively. foliage comes from foil, which used to mean “a leaf” (now obsolete), which is not surprising since it means metal rolled into thin sheets.

baggage

Baggage means “bags collectively”. Luggage is also a very similar example, but lug itself doesn’t have, or never had, any meaning as a noun (although it does make sense since it is a verb meaning “to pull”).

signage

To be honest, I “memorized” this word as “all the signs” a few months ago, but it turns out that I didn’t even need to memorize anything. (Needless to say, signage means “signs collectively.”)

wordage

Wordage means “words collectively”, although this is not a very common term.

plumage

The word plumage means “a bird’s feathers collectively”, which of course comes from plume.

others

I think that usage and language can be interpreted in the same way. (laugue has an obsolete meaning, “manner or style of expression”.)