from what place, source, or cause
"The detective questioned the witness to ascertain whence the mysterious funds had originated."
From where; from which place or source.
"The traveler asked whence he came, though his accent gave him away as being from the north."
Used for introducing the result of a fact that has just been stated.
"The data showed a sharp decline in sales, whence management decided to halt production immediately."
Whence comes from the Middle English word whennes, which originally meant "from where." It is derived from Old English and combines the word for "when" with a suffix indicating location or origin.