1. Terms and words
Terms may coincide with words in general language. Their precise meaning depends on their context or usage in a specialized subject field.
A term may contain symbols and have variants, such as abbreviations:
clippings, e.g. lab for laboratory;
blendings, e.g. motel for motor+hotel;
initialisms, made from initial letters of several words, pronounced as the alphabetic names of the letters, e.g. NBC, National Broadcasting Company, or ADHD, Attention Deficit Hyperactivity Disorder;
acronyms, these too made from initial letters but pronounced as words, e.g. NATO, North Atlantic Treaty Organization.
Terms can also have different forms of spelling (morphological variants), e.g. oedema/edema , oestrogen/estrogen, hyperglycaemia/hyperglycemia
In specialized language, terms have some specific characteristics:
precision,
emotional neutrality
stability over time

2. Terms can belong to any of the open word classes (nouns, verbs, adjectives, adverbs), though 80% or more in any given field are nouns.
in a terminology management system (TMS) aimed at translation, adjectives and adverbs are often not included in the system because their meaning can change slightly depending on the context in which they are used. Consequently, it can be difficult to determine target language equivalents.

3. Terms as designations of concepts
Sharing terms – or, even better, terminological data - makes it possible for everyone to use the same words to designate the same concept, thus avoiding problems in translation.
Terminological data include: entry term (including word class); definition; context; subject field; variant/s; equivalent/s; sources.

4. What is a concept?
A concept is a unit of knowledge created by a unique combination of characteristics (ISO 1087:1-2000).
It can refer to something material, immaterial or even imagined.
Within terminology management concepts are the units to which terms are designated.
When a concept is named, the word (term) is a label.
The label for most concepts is a single word (simple term), or more than one word (multi-word/complex term), or a symbol.
It is impossible to characterize any concept without its relation to other concepts, and in fact, in order to get information about a specific domain, subdomain or topic, mapping its concepts is essential.