An expletive attributive is an adjective or adverb (or adjectival or adverbial phrase) that does not contribute to the meaning of a sentence, but is used to intensify its emotional force.
The word is derived from the Latin verb explere, meaning "to fill", and it was originally introduced into English in the 17th century for various kinds of padding.
It was introduced into English in the 17th century for various kinds of padding—the padding out of a book with peripheral material, the addition of syllables to a line of poetry for metrical purposes, and so forth.
There are many attributive adjectives and adverbs in English that function to indicate a speaker's anger, irritation or (in some cases) strong approval without otherwise modifying the meaning of the phrase in which they occur.
For example: The phone line discussed may have, before it was cut off, been just as good as any other, so would not have been wretched in the literal senses of "extremely shoddy", "devoid of hope" or similar.