Meliorative
The adjective (and noun) meliorative comes from the Latin melior, meaning 'better', through the past participle melioratus of the verb meliorare, 'to make better', and 'to become better'. The virtually identical ameliorative is very slightly newer, and is becoming more common in the UK. In the US, meliorative is unknown to On-line Merriam-Webster (20216). Similar observations apply to the verb 'to meliorate' and the noun melioration.
In English, [a]meliorative is used of words and expressions. It means that they 'show something in a good light' or 'make things look good'. Synonyms include 'congratulatory', 'approbatory', 'complimentary' and the participles 'bettering' and 'improving'.
There are many areas of life for which different words exist. Which word one uses depends on one's point of view. At times, they show one's prejudices, or at least an ideological position. People on the same side as what a neutral might call a 'guerrilla fighter' may call him melioratively a 'freedom fighter'; his enemies may call him, pejoratively, a 'terrorist'.
- Note on pronunciation: say '[er-]meal-i-er-ate-ive', IPA: /[ə] ˈmiːl ɪ ər ˌeɪ tɪv/.
See also the antonym pejorative.