I need the Latin translation for the word "showcase". I should use it in a blog, replacing the English word to indicate a collection of products or things to be shown to all the visitors.
You have a couple options.
First, more plainly, you have conlectio, which simply means a gathering together. In rhetoric, though, it can also mean a summary of arguments (because a summary is a short collection of what was said before).
You could similarly use conceptus, but instead of the nifty summary definition, you get pregnancy instead. It still can mean simply a collection or gathering together.
You also have conlatio. Like conlectio, it can mean a gathering together of anything, but has the bonus of tending to mean ordered as well, which from there also extends to comparison of things.
I wouldn't go with any of these, but I am giving you them anyway.
To get choicest in that collection, you'll probably want to go with electa or electio. These have the added meaning of a collecting the best or quality selections.
If you want to be extra fancy, you could do what the ancients did when they gathered together the poems and use anthologia (from the Greek for "flower-gathering"), e.g. with the Anthologia Graeca (Greek Anthology) or Anthologia Latina (Latin Anthology), collections of short poems by both major and minor authors.
The Romans sometimes translated anthologia as florilegium, which was the word used during the Medieval age for a collection of excerpted writings.