Because "uva" can be grape or grapes and "cenoura" is carrot or carrots, I wrote "We eat peppers", thinking that "pimenta" could mean bell peppers. We used to have cooked sliced meat with pieces of bell pepper in it that was called pimento loaf.
It was accepted, now you say that uma pimenta is not a pimento. It works because a recipe can include different sorts of pepper, black pepper, white pepper, paprika, smoked paprika, and chilis.
Just as you wrote in English...
...different sorts of pepper, black pepper, white pepper, paprika, smoked paprika, and chilis.
...so does the Portuguese have different names for all those. For instance, pimenta branco = white pepper while piri piri is a hot pepper similar to cayenne. pimento padrão is the basis for a popular Iberian dish:
https://en.wikipedia.org/wiki/Piri_piri (well, it appears the English text for this was run through google translate from perhaps the original Portuguese because the making of the sauce translates very poorly calling for bell peppers).
Generally in EU PT at least, a spicy pepper (chili) will generically be called, "piri piri" or "malagueta" even if not the same variety (but they do also know cayenne/caiena for instance):
In Portuguese outside of Brazil, "pimento" is for fresh peppers (not peppercorns) and this includes, "pimento verde" (green bell pepper) and "pimento vermelho" (red bell pepper) while "pimentão" is for processed peppers such as a pepper paste, or powdered peppers.
For paprika there is páprica (BR PT) or paprica (EU PT), picante (hot/spicy), doce (sweet), fumada (smoked) or simply, pimentão doce (at least in EU PT) for instance since generally paprika means from Hungary. In Portugal the sweet variety is also called, colorau or colorífico when used as a garnish and not so much for taste (or add "picante" to get the spicy kind).
- pimenta = pepper from peppercorns (piper plant) in EU PT/ but in BR PT all pepper forms can fall under this name (except bell pepper).
- pimento (EU PT) is the fresh fruit from the capsicum plant, while in EU PT, pimentão means processed "pimento" pepper specifically. However, in Brazil, "pimentão" means bell pepper (or sweet pepper, as opposed to spicy chili). Also as an exception, the Azores islands will often say "pimenta" like the Brazilians for chili pepper.
In Brazil they will say the name of the pepper after the word for pepper, or having established context. For instance, "red pepper flakes" like those put on pizza is, "pimenta calabresa" with "calabresa also being the name of a sausage.
And peppercorns in Brazil are, pimenta do reino presumedly followed by the color... but this is complicated by Brazil having a native "peppercorn" tree that is not related to either of the other peppers. It grows the pink peppercorns we see in mixes.
But, these are 3 different words with many modifiers. However, even the Portuguese speakers mix these all up so a google search will find any and all of these (and machine translating is not helping in this case as we saw with the Wiki page for Piri Piri – it is worse for some others). ::sigh::
As for the singular vs plural across the languages, English has similar. A carrot cake is made with/from carrot regardless of how many it takes. In general, a lot of the non-plurals used in Brazil like sapato and calça (meaning a pair of shoes or pair of pants) are sapatos and calças* outside of Brazil (though not always).
In the end, in English and in Portuguese, when we sprinkle the spice over our food, it is pepper not peppers (pimenta not pimentas).
Just to be a little clearer, the chili pepper aka capsicum which comes from the Latin name (aka binomial scientific name) includes the bell pepper but not all peppers of the capsicum genus are bell peppers (peppers are however related to tomatoes and potatoes as well as eggplant; all in the Nightshade family aka Solanaceae):
Peppers are commonly broken down into three groupings: bell peppers, sweet peppers, and hot peppers. Most popular pepper varieties are seen as falling into one of these categories or as a cross between them.
The reason they are commonly called "pepper" is because Columbus was looking for India in order to trade which was driven in large part by spices including the pimenta (Latin = piper) pepper[corn].
Christopher Columbus was one of the first Europeans to encounter them (in the Caribbean), and called them "peppers" because they, like black pepper of the Piper genus known in Europe, have a spicy, hot taste unlike other foodstuffs. Upon their introduction into Europe, chilies were grown as botanical curiosities in the gardens of Spanish and Portuguese monasteries. Christian monks experimented with the culinary potential of chili and discovered that their pungency offered a substitute for black peppercorns.
The tastes (spiciness) though are produced by different chemicals, piperine versus capsaicin.
To get really technical (I guess beyond just nerdy), the chile peppers are a fruit with multiple seeds inside, and the peppercorns are a drupe (like a plum, peach, and even more similar like berries... of which a strawberry is not) .
Some people react violently to bell peppers but are fine with other kinds of peppers. Some believe that the cause is the ripeness of the pepper so a green bell pepper (or even a jalapeño) is a problem but not the red bell.
Here is a relevant snippet from a fascinating transcript on the origin of the piment[ã]o:
BURT WOLF: The small round dry black pepper that we grind in a mill is native to India and was brought to ancient Greece and Rome by Arab traders. It was so valuable in Europe that both the Spanish and the Portuguese spent fortunes sending out expeditions to try and break the Arab monopoly
BARBARA KETCHAM WHEATON ON CAMERA: The king and queen of Spain were anxious to get a new route to the, spice islands of the East Indies, by sailing West. Because, due to political disruption in Asia, the traditional spice routes were breaking down, and it was getting increasingly complicated to get spices from the West.
BURT WOLF: Columbus made an entry in his diary that described the chili pepper as more valuable than the black pepper and pointed out that the natives constantly used it and thought it had health-giving properties. He estimated that each year, 50 ships filled with chili peppers could be sent back to Spain and they would prove to be exceedingly profitable.
Finally, to make this even longer than I had intended, the Pink Peppercorn (Schinus) is not related to either but rather to the cashew and originates from South America including Brazil:
In Portuguese, «pimenta» is "table pepper," what you find next to the "table salt." «o pimentão» (Brazilian Portuguese) or «o pimento» (European Portuguese) is any bell pepper or, by generalization, any of the other bigger and not-ground peppers. «a malagueta» is a type of chili pepper.
I discussed this some time ago with Paulenrique. I thought at that time that "pimenta" could also translate as chile pepper http://apaixonados2.cdn.sloja.net/1152-thickbox_default/jogo-chocolate-com-pimenta.jpg
Note that some Americans spell it as "chili" and other Americans spell it as "chile"