Denotation - The literal or primary meaning of a word, in contrast to the feelings or ideas that the word suggests.
Connotation - A connotation is a commonly understood cultural or emotional association that any given word or phrase carries.
Slang - A type of language consisting of words and phrases that are regarded as very informal, are more common in speech than writing, and are typically restricted to a particular context or group of people.
Jargon - Special words or expressions used by a profession or group that are difficult for others to understand.