Adverb
1. back
2. backwards, rearward, rearwards, backwards
3. back
Adjective
1. backward
2. backswept, sweptback, cacuminal, retroflex, converse, reversed, transposed, inverse, reverse, negative, rearward, reverse, receding, reflexive, self-referent, retracted, retral, retrograde, retroflex, retroflexed, returning, reversive, regardant, regressive, retrospective, backward
3. bashful, blate, timid, feebleminded
3. retarded