The lack of any ancient denotation of anthropology, however, is not an etymological problem. Liddell and Scott list 170 Greek compounds ending in "–logia", enough to justify its later use as a productive suffix. The ancient Greeks often used suffixes in forming compounds that had no independent variant. The etymological dictionaries are united in attributing "–logia" to "logos", from "legein", "to collect". The thing collected is primarily ideas, especially in speech. The American Heritage Dictionary says: "(It is one of) derivatives independently built to logos." Its morphological type is that of an abstract noun: log-os > log-ia (a "qualitative abstract")