Concept: adjunct

Definition

An adjunct is an expression that (i) can be °focused, and (ii) that is not a °nominal or °clausal °argument, a part of a nominal, a °verb, or a °nonverbal predicate.

Croft's comparative concept

(adjunct):

adjunct = a term that is sometimes used for an oblique argument phrase denoting certain participants that are more peripheral than other participants denoted by oblique phrases, and which is therefore syntactically “optional.” Semantically, there is no clear division between peripheral participants that motivates an (oblique) argu- ment / adjunct distinction. Also, the phrases expressing even central participants that are highly salient may be morphosyntactically “optional,” as is found with zero anaphora. There is no clear comparative concept of ‘adjunct,’ and the term is not used in this textbook.

Wikipedia

adjunct (grammar)

SIL Glossary

adjunct

Quotation

"At the beginning of the discussion of the argument/adjunct distinction stands a simple observation: some linguistic expressions in a clause are central to the predicate, i.e. they ‘complete’ the predicate, and their referents are equally central to the situation referred to by the predicate. In contrast, other linguistic expressions are peripheral to the predicate and the participants they denote pertain to the situation as a whole (cf. Dowty 2000). The former type of linguistic expression is often called ‘arguments’ (or ‘complements’), and the latter type ‘adjuncts’ (or ‘modifiers’)." (Forker 2014: 27)

Sources

Forker 2014; Dowty 2000