fántǐ (fán·tǐ complicated; complex; difficult · {body → [style] → [typeface; font]} → [traditional Chinese] 繁体 繁體) zì (characters 字) ← Tap/click to show/hide the “flashcard”
For a long, long, long time, Chinese characters were just Chinese characters. Then, in the 1950s, the Communist government of mainland China issued what came to be known as the First Chinese Character Simplification Scheme (a second round of Chinese character simplification was later attempted and ultimately rescinded), and official simplified Chinese characters came into the world. (Some characters had been unofficially simplified and used for various purposes, both everyday and artistic, before that.)
To distinguish these newfangled official simplified Chinese characters from the Chinese characters that had existed before, and that continue to be used by many people in many parts of the world, retronyms were coined to refer to these pre-existing Chinese characters, just as the term “acoustic guitars” was coined to refer to regular non-electric guitars after electric guitars came along.
In the English-speaking world, the pre-official simplification characters have come to be called “traditional Chinese characters”, as opposed to the “simplified Chinese characters”. In the Chinese-speaking world, as is true of many things regarding Chinese characters, the situation is…complicated. Wikipedia summarizes the situation thusly:
Traditional Chinese characters (the standard characters) are called several different names within the Chinese-speaking world. The government of Taiwan officially calls traditional Chinese characters standard characters or orthodox characters (traditional Chinese: 正體字; simplified Chinese: 正体字; pinyin: zhèngtǐzì; Zhuyin Fuhao: ㄓㄥˋ ㄊㄧˇ ㄗˋ).[source] However, the same term is used outside Taiwan to distinguish standard, simplified and traditional characters from variant and idiomatic characters.[source]
In contrast, users of traditional characters outside Taiwan, such as those in Hong Kong, Macau and overseas Chinese communities, and also users of simplified Chinese characters, call them complex characters (traditional Chinese: 繁體字; simplified Chinese: 繁体字; pinyin: fántǐzì; Zhuyin Fuhao: ㄈㄢˊ ㄊㄧˇ ㄗˋ). Users of simplified characters sometimes informally refer to them as “old characters” (Chinese: 老字; pinyin: lǎozì; Zhuyin Fuhao: ㄌㄠˇ ㄗˋ).
Users of traditional characters also sometimes call them “full Chinese characters” (traditional Chinese: 全體字; simplified Chinese: 全体字; pinyin: quántǐ zì; Zhuyin Fuhao: ㄑㄩㄢˊ ㄊㄧˇ ㄗˋ) to distinguish them from simplified Chinese characters.
In my experience in the Chinese fields in Canada, I have always heard traditional Chinese characters referred to using this week’s MEotW, “fántǐ (fán·tǐ complicated; complex; difficult · {body → [style] → [typeface; font]} → [traditional Chinese] 繁体 繁體) zì (characters 字)”. For reference, this is also the term used on jw.org when referring to Mandarin written using traditional Chinese characters:
jw.org refers to traditional Chinese characters as “fántǐ (fán·tǐ complicated; complex; difficult · {body → [style] → [typeface; font]} → [traditional Chinese] 繁体 繁體)” characters.