bottom-up (adj.)

In several branches of LINGUISTICS, a term which informally characterizes any procedure or MODEL which begins with the smallest functional UNITS in a HIERARCHY and proceeds to combine these into larger units; opposed to top-down, which begins with the analysis of a high-level unit into progressively smaller units. For example, in GRAMMAR, models which begin with MORPHEMES or WORDS are ‘bottom-up grammars’, those which begin with SENTENCE, CLAUSE, or some DISCOURSE unit are ‘top-down grammars’. The distinction is also used in the analysis of text structure in textlinguistics and STYLISTICS, in some approaches to NON-LINEAR PHONOLOGY, in the teaching of reading (phonics v. whole word), and also in relation to models of mental PROCESSING in PSYCHOLINGUISTICS and PARSING procedures in COMPUTATIONAL LINGUISTICS.