'portent' is the definition.
(synonyms)
This is all the clue.
(Other definitions for omen that I've seen before
include
"Foreboding"
,
"Portent, prophetic sign"
,
"Sign of likely future event"
,
"Forewarning, harbinger"
,
"Event regarded as a prophetic sign of good or evil"
.)
I've seen this clue in the Sydney Morning Herald, the Evening Standard, The Mirror, The Telegraph, The Independent, The Sun, The Times, the King Feature Syndicate, The Sunday Times, The New York Times, The Star Tribune, The Wall Street Journal, The Guardian and the Penny Press.
'portent' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for sign that I've seen before
include
"Public notice; gesture"
,
"Engage by written agreement"
,
"Endorse"
,
"Indicator"
,
"Augury"
.)
I've seen this clue in the Sydney Morning Herald, the Evening Standard, The Mirror, The Telegraph, The Independent, The Sun, The Times, the King Feature Syndicate, The Sunday Times, The New York Times, The Star Tribune, The Wall Street Journal, The Guardian and the Penny Press.