* Idioms: These are phrases that have a figurative meaning different from the literal meaning of the individual words. Examples: "kick the bucket", "bite the bullet", "spill the beans".
* Slang: This refers to informal language used within a particular group, often to communicate in a way that outsiders don't understand. Examples: "chill", "lit", "bae".
* Catchphrase: This is a short, memorable phrase that is often used by a particular person or character, and becomes associated with them. Examples: "I'm lovin' it" (McDonald's), "Just do it" (Nike), "Live long and prosper" (Star Trek).
* Verbal tic: This is a repeated word or phrase that is often used unconsciously, and can sometimes be a sign of anxiety or nervousness. Examples: "like", "um", "you know".
* Pet phrase: This is a word or phrase that a person uses frequently, and often with a particular meaning or emotion attached to it. This term is less specific than "catchphrase" and doesn't necessarily imply memorability or widespread use. Examples: "Absolutely!" "Oh my goodness!"
In the case of "okie dokie", this is an example of slang and a pet phrase. It's informal and used to express agreement or understanding, often in a playful or friendly way.
Ultimately, the most accurate term will depend on the specific words or phrases in question and the context in which they are used.