abate arrest backpedal backwater bate brake check clip the wings curb decelerate delay detain draw rein ease ease off hold back hold in check hold up impede keep back let down let up let up on loose loosen lose ground lose momentum lose speed mitigate moderate obstruct reef rein in relax remit retard set back slack slack off slack up slacken slake slow slow down slow up stay take in sail throttle down unbend unbrace unlax unstrain unstring unwind