In a manner that functions as an attribute; in the grammatical position of modifying a noun directly.
From 'attributive' plus '-ly' adverb suffix. Describes how something operates or functions in the attributive manner.
When linguists describe how words function 'attributively,' they're talking about grammar positioning. 'Old age' uses 'old' attributively, but 'age is old' uses it predicatively—the meaning barely changes, but the grammar rule is totally different!
Complete word intelligence in one call. Free tier — 50 lookups/day.