-ical

(Latin: from -icalis, a suffix that forms adjectives from nouns; of or having to do with; having the nature of; constituting or being; containing or made up of; made by or caused by; like, characteristic of; art or system of thought; chemical terms)

electrotechnical
1. Having to do with electrotechnology or the science that deals with the practical applications of electricity.
2. The study or science of practical and industrial applications of electricity.
empirical
encyclical (s) (noun), encyclicals (pl)
entomological (adjective), more entomological, most entomological
1. A reference to the study of insects or some aspect of insect studies.
2. Of or relating to the biological science of bugs.