Although it’s “absorbed” and “absorbing” the correct spelling of the noun is “absorption.”
But note that scientists distinguish between “absorption” as the process of swallowing up or sucking in something and “adsorption” as the process by which something adheres to the surface of something else without being assimilated into it. Even technical writers often confuse these two,.
RSVP stands for the French phrase répondez s’il vous plaît (“reply, please”) so it doesn’t need an added “please.” However, since few people seem to know its literal meaning, and fewer still take it seriously, it’s best to use plain English” “Please reply.” And for those of you receiving such an invitation, yes, you have to let the host know whether you are coming or not, and no, you can’t bring along the kids or other uninvited guests.
When you grind coffee beans the result is fresh grounds. How finely you grind them determines what grind you produce, such as a coarse or medium grind. In this sense the noun “grinds” can refer only to the size of the coffee granules, not to the granules themselves.
Some people like to put their used grounds into the ground to fertilize their plants.
But fresh or used, that ground-up stuff is not “grinds” but “grounds.”
Another example of the oral transformation of language by people who don’t read much. “For all intents and purposes” is an old cliche which won’t thrill anyone, but using the mistaken alternative is likely to elicit guffaws.