Synonyms for Warning (same or very similar meaning)
WordNet sense 1 (cautionary advice about something imminent (especially imminent danger)):
admonition, monition, word of advice
WordNet sense 2 (serving to warn):
admonitory, cautionary, exemplary, monitory
WordNet sense 3 (deterring from action):
dissuasive
From the ODE community, based on WordNet
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