-al; -ial, -eal

(Latin: suffix; pertaining to, like, of the kind of, relating to, characterized by, belonging to; action of, process of)

thermal (adjective) (not comparable)
1. Relating to or involving heat or changes in heat: The family was interested in thermal insulation when building their new home.
2. Of, pertaining to, or of the nature of hot springs; of a spring, etc., (naturally) hot or warm: When staying at the spa town, Jill wanted to go to the thermal baths which contained warm water from the nearby hot springs.
3. Regarding clothes designed to keep a person warm in cold weather: Lynn bought a thermal coat before she went to see her family in Toronto for Christmas.
4. Of or pertaining to heat; determined, measured, caused, or operated by heat: Virginia bought a thermal blanket which provided lots of warmth when plugged into a socket and switching on.
thermal (s) (noun), thermals (pl)
A movement or rising warm air: A thermal is a localized air current that rises aloft when the lower atmosphere is heated enough to produce an instability over a certain area.

When a thermal, or current of relatively warm air rises, it is advantageous for gliders and birds to gain height.

verbal (adjective) (not comparable)
1. Dealing in or with words, especially with mere words in contrast to things or realities: The new job requires someone with strong verbal skills.
2. Pertaining to the use of many words; talkative, verbose: Sometimes Alice is just too verbal and never seems to know when to stop talking.
3. Regarding the interest in the mere words of a literary composition: Ton's composition turned out to be full of clever verbal expressions.
4. Consisting or composed of words; of or pertaining to, manifested in, words: The two students had a verbal agreement to start the project.
5. In diplomacy, a spoken or oral and unsigned note: A verbal memorandum can be sent as a mere reminder of some matter not of immediate importance.
6. Concerning a tendency to talk too much; extreme verbosity: Sally was constantly chatting to others or to herself and her friends termed her as having a case of verbal diarrhea!
7. A reference to something that is expressed or conveyed only by speech: Verbal communication takes place instead of writing and stated or delivered by word of mouth.
visual (adjective), more visual, most visual
1. Regarding something that can be seen, or that is intended to be seen, by the eyes: The visual presentation by using a large computer screen was welcomed by all the teachers in the meeting.

Visual material can be a photograph, a picture, a chart, a graph or other kinds of presentations that display information or promotional matter in a way that appeals to the sense of sight.
2. Relating to the sense of sight: In class, the students learned many aspects of the visual organs of a person, like the visual receptors on the retina.
3. Able to be perceived as a picture in the mind rather than as an abstract idea: Carol was known for having a visual memory.

vital (adjective), more vital, most vital
1. Relating to, or characteristic of life: Vital process take place in the body, like the vital red fluid that flows in the veins and arteries. .
2. Referring to essentials in life; of utmost importance; necessary to maintain life: Certain vital processes, as , breathing, eating, and drinking, are just a few of the things that are vital functions of life.