note
A type of tremolo for eighth notes, like a quivering note, represented by two thick lines drawn through the stem.
Popcorn by Hot Butter
I believe your speaking of the symbol called Luvanmusiq, from Musiq soulchild's album named Luvanmusiq.
Their cat is called Armani :) (Which sounds so cute when you say it with their accent ;D)
b.e.a.t
An unknown number represented by a letter or symbol is a variable.
That is the chemical symbol of an element, such a H for hydrogen, Hg for mercury, etc.
A long vowel sound is marked by a bar across the top, called a macron.
Phonology is the study of speech sounds in a particular language. The vowel sound in the word herd is represented by the phonetic symbol called a schwa.
the sh was represented by a horizontal rectangle, called a "garden pool" 
Is called a variable and is represented by and letter
Aries' symbol is the ram.
Be is the chemical symbol for Beryllium.
In general density is represented by the Greek symbol rho (ρ)
The symbol used on Passover is called maror (מרור) in Hebrew, which is usually represented by horseradish or lettuce.
The currency used in China is called the Chinese Yuan, and it is represented by the symbol ¥.
The symbol used to indicate the end of a piece of music in sheet music is called a double bar line, represented by two vertical lines.