1. Yet another metasyntactic variable (see foo). It is reported that at CMU from the mid-1970s the canonical series of these was "foo", "bar", "thud", "blat".
2. Rare term for the hash character, "#" (ASCII 35). See ASCII for other synonyms.
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Nearby terms: three-letter acronym « three-tier « throughput « thud » Thumb » thumb » thumbnail