The following article mentions the origin of the word mole, quoting from the original documents:
"Mole and Chemical Amount: A Discussion of the Fundamental Measurements of Chemistry" by George Gorin (Journal of Chemical Education, vol. 71 No. 2, p. 114-116, Feb. 1994)
On p. 116, Gorin writes:
The unit "mole" was introduced into chemistry around 1900 by Ostwald, and he originally defined this unit in terms of gram. Gram is a unit of mass; but what is the mole a unit of? Ostwald did not say;3 however, several years later, he did make it clear that the concept of mole should be linked to the ideal gas. 4
3"...the molecular weight of a substance, expressed in grams, shall henceforth be called mole [. . . das in Grammen augedruckte [. . .] Molekulargewicht eines Stoffes soll fortan ein Mol heissen]" Ref. 7).
4 "That amount of any gas that occupies a volume of 22414 mL in normal conditions is called one mole [eine solche Menge irgendeines Gases, welche das Volum von 22412 ccm im Normalzustand einnimt nennt man ein Mol]" (Ref. 8)
Ref. 7. Ostwald, W. Grundriss der allgemeinen Chemie; Leipzig: Engelmann, 1900, p. 11
Ref. 8. Ostwald, W. Grundriss der allgemeinen Chemie, 5th ed.; Dresden: Steinkopff, 1917, p. 44