Glossary
Searchable terminology from accessibility, web standards, and related fields.
44 results found in Natural Language Processing.
- Lexical Chain (Lexical Chaining, Lexical Cohesion)
- A sequence of semantically related words running through a text — for example, "doctor", "hospital", "nurse", "patient" — connected by relations like synonymy, hypernymy, or hyponymy. Lexical chains c…
- Lexical Simplification (Word-Level Simplification)
- A form of text simplification that focuses on replacing complex, uncommon, or technical words with simpler, more familiar alternatives. Lexical simplification is particularly relevant for readers with…
- Machine Translation (MT, Automated Translation)
- Machine translation is the use of computer software to automatically translate text or speech from one language to another. In accessibility contexts, machine translation is particularly relevant to s…
- Multimodal Natural Language Generation (Multimodal NLG)
- Natural language generation systems that produce output coordinated across more than one modality — typically combinations of text or speech with graphics, maps, animation, gesture, or tactile output.…
- Part of Speech (POS, Word Class, POS Tag)
- A grammatical category assigned to each word (or, in signed languages, each sign) in a sentence — such as noun, verb, adjective, adverb, pronoun, preposition, or conjunction. Automatic part-of-speech …
- Part-of-Speech (POS, Word Class, Lexical Category)
- The grammatical category of a word — noun, verb, adjective, adverb, preposition, pronoun, conjunction, determiner, and so on. Part-of-speech labels are the basic output of part-of-speech tagging and a…
- Part-of-Speech Tagging (POS Tagging, Grammatical Tagging)
- Part-of-speech tagging is the natural-language-processing task of labelling each word in a text with its grammatical category — noun, verb, adjective, and so on — using context from surrounding words.…
- Perplexity (Language Model Perplexity)
- A standard metric for evaluating language models that measures how well the model predicts a sample of text. Mathematically, perplexity is the inverse probability of the test set, normalised by the nu…
- Pointwise Mutual Information (PMI)
- A statistical measure used in natural language processing to quantify the strength of association between two words based on how much more frequently they co-occur in a corpus than would be expected b…
- Pronominal Reference (Pronoun Reference, Anaphoric Reference)
- The use of pronouns or pronoun-like expressions to refer back to entities previously introduced in a discourse. In spoken and written languages this is typically achieved with words such as "he," "she…
- Semantic Disambiguation (Word Sense Disambiguation)
- Semantic disambiguation is the process of determining the intended meaning of a word, symbol, or input when multiple interpretations are possible. In accessibility and assistive technology contexts, s…
- Semantic Relatedness (Semantic Similarity, Semantic Association)
- A measure of how closely related two words or concepts are in meaning, encompassing various types of relationships including synonymy, hyponymy, meronymy, and general topical association. In assistive…
- Sequence-to-Sequence (Seq2Seq, Encoder-Decoder)
- A neural network architecture designed for tasks where both input and output are sequences of variable length, such as machine translation, speech recognition, and video captioning. A seq2seq model co…
- Sign Language Machine Translation (English-to-ASL Translation, Sign Language MT, Text-to-Sign Translation)
- The automatic translation of written or spoken text into a signed language (or vice versa) using computational methods, typically producing output as an animated signing avatar or, less commonly, as r…
- Stemming (Word Stemming, Suffix Stripping)
- Stemming is a natural-language-processing technique that reduces inflected or derived words to their base or root form — 'running', 'runs', and 'ran' all map to the stem 'run'. The Porter stemmer (198…
- Syntactic Parse Tree (Parse Tree, Syntactic Tree)
- A tree-shaped data structure that represents the grammatical structure of a sentence according to a formal grammar. Internal nodes correspond to phrases (noun phrase, verb phrase, clause, sentence) an…
- Syntactic Simplification (Sentence Simplification)
- A form of text simplification that restructures complex sentences into simpler grammatical forms, such as splitting compound sentences, converting passive voice to active voice, or resolving relative …
- Text Alignment (Sequence Alignment, Transcript Alignment)
- The process of matching corresponding segments between two or more text sequences that represent the same content but may differ in timing, wording, or structure. In captioning systems, text alignment…
- Transfer Machine Translation (Transfer MT, Rule-Based Transfer Translation)
- A rule-based machine-translation paradigm that analyses the source text into a syntactic or semantic structure, applies a set of transfer rules to produce a corresponding structure in the target langu…
- Transformer (Transformer Model, Transformer Architecture)
- A deep learning architecture introduced by Vaswani et al. in 2017 that relies entirely on attention mechanisms rather than recurrence (RNNs) or convolution for sequence modeling tasks. Transformers pr…