What is the gram­mat­i­cal term for “‑ed” words like these?

Solution 1:

They are called the Past Participle. They can either be formed by adding the suffix ed

or be an irregular such as: eat-> eaten -> fight -> fought (not to be confused with The Past Simple which is simply the verb of past simple tenses clauses.

They can be many things in English.

just to name a few:

• an adjective
• the perfect module verbs
• passive voice

Solution 2:

The -ed in all of your examples is a past-participle suffix. A past participle is not a derived form: rather, it is an inflected form of a verb (assuming you accept the distinction between derivation and inflection as grammatical processes in English). Most past participles end in -ed, but some end in -⁠(e)n instead (like beaten) and some don't end in either -ed or -(e)n (like stood or hurt). The past participle can have a passive meaning, so it can also be called a "passive participle". In the context of English, "past participle" and "passive participle" refer to the same verb form.

But not all words ending in -ed are verb forms. Words belonging to other parts of speech can be derived from past participles. I think the most common type of derivation is past participle → adjective. Since verbs and adjectives are distinct parts of speech, it's best not to refer to such adjectives as "participles": instead, they can be called departicipial adjectives (a synonymous term is "participial adjectives"), which lets us reserve the term participle for the inflected form of the verb. That said, it's not always possible to figure out whether a word is a participle or a departicipial adjective.

Here are some common texts for finding out whether a word is an adjective or a verb:

• Can it be preceded by very? If so, it's an adjective. This test doesn't give positive results for me for any of your phrases. (But note that this test only works one way: it can't tell you that a word isn't an adjective. There are some adjectives that can't be preceded by very.)

• Can it be preceded by carefully? If so, it's a verb. For me, this test indicates that the -ed words in all of your examples could be verbs.

• Can you add the prefix un- (with the sense of "not", not with a sense of reversal)? If so, it's probably an adjective. For me, this test indicates that calibrated at least can be an adjective (since we certainly can say "an uncalibrated device"). The situation is less clear for distributed, destroyed and founded. There are dictionary entries for undistributed and undestroyed, but "an undistributed product" and "an undestroyed house" both sound a bit weird to me. Unfounded clearly exists as the negation of a different sense of the word founded, but *"an unfounded com­pany" doesn't seem acceptable to me.

There are other possible tests, but I can't describe all of them. Some sources suggest that word order might be relevant, but I believe this is a mistaken view, so I haven't included this as a test.

I think I've made it clear from what I've said above that there are many words ending in -ed that are not past participles/passive participles. (Most obviously, many past-tense verb forms end in -ed, but they are definitely not participles.)