Webster's 1828 Dictionary
FOREWARNING
ppr. Previously admonishing or informing.
FOREWARNING
n.Previous admonition, caution or notice.
New American Oxford Dictionary
forewarning
fore warn ing |fôrˈwôrniNG | ▶noun an advance warning: officials had no forewarning of the attacks.
Oxford Dictionary
forewarning
fore |warn |ing |fɔːˈwɔːnɪŋ | ▶noun an advance warning: officials had no forewarning of the attacks.
American Oxford Thesaurus
forewarning
forewarning noun the dogs howled a forewarning of death: omen, sign, indication, portent, presage, warning, harbinger, foreshadowing, augury, signal, promise, threat, hint, straw in the wind, writing on the wall, canary in the coal mine; literary foretoken.
Oxford Thesaurus
forewarning
forewarning noun when dogs howled at night it was a forewarning of death: harbinger, omen, augury, sign, signal, herald, indication, presage, portent, promise, prediction, forecast, premonition; warning, advance warning, prior warning; informal tip-off; literary foretoken.
The Wordsmith Dictionary