(Greek: didaktikos, skilled at teaching, teach; teacher)

autodidact (s) (noun), autodidacts (pl)
A self-taught person or those who have taught themselves without formal instructions: Some autodidacts spend a great deal of time in libraries, on educational websites, or seeking information from those who are specialists in the fields of their interests.

Many autodidacts, depending on their plan for learning, seek instruction and guidance from experts, friends, teachers, parents, siblings, and from other sources within their communities.

autodidactic (adjective), more autodidactic, most autodidactic
Relating to or characteristic of being self-taught: The autodidactic education that Sam acquired during the years he was being homeschooled are considered quite superior.
autodidactically (adverb), more autodidactically, most autodidactically
A reference to instructing oneself or learning things as a person determines what is the best way to acquire an education: Sarah autodidactically learned to become a professional pianist with tutoring from a piano teacher and professional musicians.
autodidacticism, autodidactism (s) (noun) (usually no plural form)
Self-education, self-study, or self-directed learning: Sara was helping her children to use autodidacticism as their main educational process by spending a great deal of time on educational web sites and by buying books that deal with various vocational fields so they can decide what they want to do in the future.

Autodidactism is just one way of learning, and it is usually complemented by learning in formal and informal settings; such as, classrooms, friends, family, social settings, and experts or people with special training.

didactic (adjective), more didactic, most didactic
1. Intended to be educational or tending to give instruction or advice, even when it is neither welcome nor necessary: The novel was somewhat entertaining, but it had an underlying didactic message that indicated we could learn much from history.

Some language reference books these days are considered to be less didactic than they once were.

3. Inclined to teach or to moralize excessively: The technician's didactic explanations irritated his coworkers, who simply wanted to be told how the software worked, without having to listen to long explanations about the theory and history regarding its development.
3. Containing a political or moral message: The politician's didactic speeches were usually told with the pretext of entertainment, but it was obvious that he wanted his audience to receive some moral messages from them, too.
didactically (adverb), more didactically, most didactically
Designed or intended to educate and to convey instruction and information: Teachers are likely to talk didactically.

Fortunately Professor Jones didactically lectured about the most significant problems presented by the economists.

didacticism (s) (noun) (usually not plural)
A form of communication that is suitable for or intended to be instructive: There is a certain amount of didacticism that is expected in books for young people.

In early English poetic literature, and especially in the religious parts of it, there are elements of didacticism that we should be aware of.

An essay by Edgar Allan Poe argues that a poem should be written "for a poem's sake" and that the ultimate goal of art is aesthetic and not didacticism, which he called a "heresy".

nondidactic (adjective) (not comparable)
Being taught by experiences rather than by formal educational institutions: Some people have prepared themselves for life and jobs by means of nondidactic learning experiences.
nondidactically (adverb), more nondidactically, most nondidactically
A reference to informal or noninstitutional learning: Living out in a wilderness situation far from schools, the children nondidactically learned to read and to write with help from their parents who provided a variety of books.
tachydidactic (adjective), more tachydidactic, most tachydidactic
Characteristic of being edified rapidly or teaching quickly: The teenagers had a tachydidactic education because their parents did not have the financial means to send them to schools for the normally extended period of educational instruction.
tachydidactically (adverb), more tachydidactically, most tachydidactically
Educating quickly because of a lack of time or a limited access to equipment; such as, computers, laboratory facilities, or other tools: With the decrease in financial resources in many places, some more intellectually endowed students are taught by tachydidactically experienced instructors.
theodidact (s) (noun), theodidacts (pl)
A student of God or someone who is enlightened by God: Henry came from a religious family of theodidacts whose lives were centered on learning and promoting the teachings of God.
undidactic (adjective), more undidactic, most undidactic
Not being formerly instructed and so getting knowledge only by means of experiences: Ted was a member of a group of people who were so segregated from other communities that they were only able to learn to survive by means of undidactic living.