Synonyms for Flat-footed (same or very similar meaning)
WordNet sense 1 (not prepared or in a state of readiness; slow to understand or respond):
unready
WordNet sense 2 (having feet that turn outward):
splayfoot, splayfooted
WordNet sense 3 (having feet):
footed
WordNet sense 4 (extended senses; direct in means or manner or behavior or language or action):
direct
From the ODE community, based on WordNet
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