por·ten·tous adjective \pȯr-ˈten-təs\: giving a sign or warning that something usually bad or unpleasant is going to happen: trying to seem important, serious, or impressive.
1: of, relating to, or constituting a portent <suspense, portentous foreshadowing, hints of sinister and violent mysteries — Francine Prose>. 2: eliciting amazement or wonder : prodigious. 3 a: being a grave or serious matter <portentous decisions> b: self-consciously solemn or important : pompous<portentous declamation unsalted by the least trace of humor — W. H. Pritchard>. c: ponderously excessive <that discipline’s overwrought, portentous phrases — R. M. Coles>
Definition source: http://www.merriam-webster.com
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