Terms can have different types of structures:
- Simple terms: Terms consisting of only one stem with or without affixes, e.g. wireless, infrared, etc.
- Abbreviated terms:
2.1) Abbreviations: Abbreviated simple terms resulting from the omission of some of its letters
2.1.1) Initialisms: Abbreviated complex terms or names made up of the first letters of the term elements (e.g. UEFA=Union of European Football Associations)
2.1.2) Acronyms: Abbreviated complex terms made up of letters from the full form of a term strung together into a sequence pronounced only syllabically (e.g. UNICEF=United Nations Children's Fund) - Complex terms: Terms consisting of two or more stems with or without other term elements, e.g. bookmarker, mother-in-law
- Compound terms: Complex terms in which the elements have a fixed position within the term as a whole but are not linked by morphological devices, e.g. power button, communication adapter unit [Source: ISO 1087, p. 8]. It is important to keep in mind that terms are not restricted to nouns or noun phrases but can also be phraseological units containing verb phrases.
The choice between a single-word or a multiword term depends on language conventions. Sometimes the equivalent of a single-word term in one language is a multiword in another language, e.g. molinillo (Spanish) and chocolate frother (English).