Guttural speech sounds are those with a primary place of articulation near the back of the oral cavity. In some definitions, this is restricted to pharyngeal consonants, but in others includes some velar and uvular consonants. Guttural sounds are typically consonants, but some vowels' articulations may also be considered guttural in nature.
Although the term has historically been used by phoneticians, and is occasionally used by phonologists today, it is now more common in popular use as an imprecise term for sounds produced relatively far back in the vocal tract. The term continues to be used by some phonologists to denote laryngeal consonants (including uvulars), as well as murmured, pharyngealized, glottalized, and strident vowels.
The word guttural literally means 'of the throat', and is derived from the Latin word for throat. In colloquial usage, the term is used for any sound pronounced in the throat or near the back of the mouth that is considered "harsh." Contrary to popular opinion, the word has no connection to the word gutter. The OED says,
Nobody took down my guard like you
Nobody moved in their toothbrush so soon
Nobody does whatever they want like you
I'm cards on the table
I am spilled milk
There's no use crying
There's forces at will
I'm yours for the taking
Come get your fill
'cause nobody loves me like you do
Nobody thrills me like you do
Nobody gets me
Nobody kills me like you
Nobody buys me old books like you
Nobody hikes up my skirt like you
Nobody says they ain't changing like you
I'm painting a picture 'cause I'm seeing red
You're not the villain I've built in my head
The flowers you picked out still sit by the bed
'cause nobody loves me like you do
Nobody thrills me like you do
Nobody gets me
Nobody kills me like you
To love you is to go mad
To love you is to lose myself
In meeting you I've met my match
There's no sweeter death
No sweeter death than this
Nobody loves me like you do
Nobody thrills me like you do
Nobody gets me
Nobody kills me like you
Nobody loves me like you do
Nobody thrills me like you do
Nobody gets me