These are Types of

This

Wedding, Birthday, Bundt

Cake

Junk, Sloop, Catamaran

Boat

Incisor, Canine, Bicuspid

Tooth

Sombrero, Beret, Fez

Hat

Cirrus, Stratus, Cumulus

Cloud

CrossCountry, Alpine, Telemark

Skiing

Challah, Focaccia, Naan

Bread

Latex, Oil, Acrylic

Paint

Katana, Sabre, Scimitar

Sword

Macaroni, Tortellini, Ziti

Pasta


These are Types of

This

Dark, Milk, Hot

Chocolate

Sock, Shadow, Marionette

Puppet

Mandarin, Cantonese, Wu

Chinese

Municipal, Corporate, Bail

Bond

Serif, Sans Serif, Decorative

Font

Ashkenazi, Sephardi, Mizrahi

Jew

Wild, Basmati, Arborio

Rice

Death, Glam, Nu

Metal

Natural, Irrational, Imaginary

Number

Concord, Globe, Muscadine

Grape


Imaginary numbers are numbers made using the imaginary unit i, which is defined as a solution for x to the equation x^2 + 1 = 0  in other words, i is the square root of 1. You can treat it like a number in terms of adding and multiplying, so 3 * i = 3i, you can also have pi * i, or 2.234837i, etc. Those are all imaginary numbers. When you add them to real numbers, you get something like 3 + 4i, which is what's called a complex number. Despite the seemingly strange definition, they're actually incredibly useful and powerful in both mathematics in general and engineering.
Irrational numbers are those that can't be expressed as the ratio of two integers. So 2/3 is rational, 4234/7437 is rational, but pi and e are both irrational, along with most other numbers.
Imaginary numbers are formed using the imaginary unit i, which you can think of as representing the square root of 1. You can treat it like a variable when it comes to multiplying and adding with other real numbers, and get things like 2i, or pi * i, or 2347i/7108. These are all imaginary numbers. When you add a real number, like 3 + 4i, the result is what's called a complex number. They're incredibly widespread in mathematics and are very useful in some engineering fields as well.
Where I live, noodle is pretty much reserved for Asian foods  soba, banh pho, or youmian. If you called spaghetti a noodle people wouldn't find that odd and agree it makes sense, it's just not the done thing. But tortellini? Not so much.
I live right next to the town that concord grapes are named after