The difference between Murder and Slay

When used as verbs, murder means to deliberately kill (a person or persons), whereas slay means to kill, murder.

Murder is also noun with the meaning: an act of deliberate killing of another being, especially a human.

check bellow for the other definitions of Murder and Slay

Murder as a noun (countable):

An act of deliberate killing of another being, especially a human.

Examples:

"There have been ten unsolved murders this year alone."
Murder as a noun (uncountable):

The crime of deliberate killing of another human.

Examples:

"The defendant was charged with murder."
Murder as a noun (uncountable, legal, in jurisdictions which use the felony murder rule):

The commission of an act which abets the commission of a crime the commission of which causes the death of a human.
Murder as a noun (uncountable, used as a predicative noun):

Something terrible to endure.

Examples:

"This headache is murder."
Murder as a noun (countable, collective):

A group of crows;

Murder as a verb:

To deliberately kill (a person or persons).

Examples:

"The woman found dead in her kitchen was murdered by her husband."
Murder as a verb (transitive, sports, figuratively, colloquial, hyperbolic):

To defeat decisively.

Examples:

"Our team is going to murder them."
Murder as a verb:

To botch or mangle.
Murder as a verb (figuratively, colloquial, hyperbolic):

To kick someone's ass or chew someone out (used to express one's anger at somebody).

Examples:

"He's torn my best shirt. When I see him, I'll murder him!"
Murder as a verb (figuratively, colloquial, British):

to devour, ravish.

Examples:

"I could murder a [[hamburger]] right now."

Slay as a verb (now, _, literary):

To kill, murder.

Examples:

"The knight slew the dragon."

"Our foes must all be slain."
Slay as a verb (literary):

To eradicate or stamp out.

Examples:

"You must slay these thoughts."
Slay as a verb (by extension, colloquial):

To defeat, overcome (in a competition or contest).
Slay as a verb (slang):

To delight or overwhelm, especially with laughter.

Examples:

"Ha ha! You slay me!"
Slay as a verb (slang, ambitransitive):

To amaze, stun or otherwise incapacitate by awesomeness; to be awesome at something; to kill .
Slay as a verb (slang):

to have sex with