rick·rack 
(rĭkrăk′)
(rĭkrăk′)n.
A flat narrow braid woven in zigzag form, used as a trimming for clothing or curtains.
[Reduplication of RACK1.]
- unsubscribe
- unsubstantial
- unsubstantiality
- unsubstantially
- unsuccess
- unsuccessful
- unsuccessfully
- unsuitability
- unsuitable
- unsuitably
- unsung
- unsure
- unsurely
- unsurprising
- unsurprisingly
- unsusceptible
- unsuspected
- unsuspectedly
- unsuspecting
- unsuspectingly
- unswathe
- unswear
- unswerving
- unswervingly
- unsworn