Iconic reduplication of verbs and adjectives is frequently attested in spontaneous usage and easily elicited. In contrast, iconic noun reduplication is only occasionally attested, and proved marginal also in that elicitation of noun reduplications was invariably rejected by speakers (see Feature 23 "Expression of nominal plural meaning").
Iconic verb reduplication is accompanied by an iterative semantic effect (punctual verbs) and/or a continuative semantic effect (nonpunctual verbs), with various secondary effects such as aimlessness and object distribution. Adjective reduplication has an augmentative or intensifying effect (gradable adjectives) and an emphatic effect (all adjectives). Finally, noun reduplication carries a distributive plural interpretation.
Word-class changing reduplication is unproductive. There are two forms which involve reduplication of this kind only; both involve the derivation of an instrument noun from verb input. They are: pundipundi 'sugar cane mill' < pundi 'to press, squeeze (juice)' and bainbain 'cover' < bain 'to cover.
Source: Kouwenberg 2003b: 260
Source: Kouwenberg 1991: 84
Source: Kouwenberg 1991: 85