technical has 6 distinct synonyms spread across 5 of its 9 senses. Each sense below keeps its own list, because a synonym belongs to a meaning and not to a word: swapping one sense's substitute into another sense's sentence is how a thesaurus makes writing worse. Its one recorded opposite is nontechnical.
Counts are distinct word forms across every sense. A synonym that appears under three senses is counted once here and shown three times below, under each sense it belongs to.
of or relating to technique or proficiency in a practical skill
“his technical innovation was his brushwork”
characterizing or showing skill in or specialized knowledge of applied arts and sciences
“a technical problem”
of or relating to a practical subject that is organized according to scientific principles
“technical college”
relating to or concerned with machinery or tools
“mechanical arts”
of or relating to or requiring special knowledge to be understood
“technical terminology”
a pickup truck with a gun mounted on it
(basketball) a foul that can be assessed on a player or a coach or a team for unsportsmanlike conduct; does not usually involve physical contact during play
2 of the 9 recorded senses carry no synonym, antonym or related term, so they are not shown above. Every sense, with its definition and examples, is on the full entry for technical.
Synonyms, antonyms and the broader and narrower relations for technical come from Princeton University’s WordNet. Full sources and licences.