Hard is a term used to refer to the taste of wine with excessive acidity and tannins.

Hard tasting wines typically are young wines which have not fully matured so the excessive tannins overpower and mask the underlying flavors and qualities that may be present as it matures.

See also:
"Hard" is in the HS Code "2620.11"
  - -- Hard zinc spelter

"Hard" is in the UNSPSC Code "43201616"
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