yesternEtymologyPerhaps from yester + -en. Compare also Old English ġiestran (“yesterday”).adjOf or pertaining to yesterday.“Argos, I fear, will pay us soon again Her yestern debt[…]”advYesterday.“"F. Newman's book I saw yestern at our ouse," Arnold writes to Clough. "He seems to have written himself down an hass.”nounYesterday.“Yestern was the day of hail, […]”