Hireling, a.
Serving for hire or wages; venal; mercenary. "Hireling mourners." Dryden.
1 other Webster entry under this spelling
Hireling, n.
One who is hired, or who serves for wages; esp., one whose motive and interest in serving another are wholly gainful; a mercenary. "Lewd hirelings." Milton.
Shades of meaning
Fernald has no entry of its own for hireling; he lists it under venal.
Where he writes about it:
Venal (L. venalis, from venum, sale) signifies ready to sell one's influence, vote, or efforts for money or other consideration; mercenary (L. mercenarius, from merces, pay, reward) signifies influenced chiefly or only by desire for gain or reward; thus, etymologically, the mercenary can be hired, while the venal are openly or actually for sale; hireling (AS. hyrling, from hyr) signifies serving for hire or pay, or having the spirit or character of one who works or of that which is done directly for hire or pay. — from venal
The hireling, the mercenary, and the venal are alike in making principle, conscience, and honor of less account than gold or sordid considerations; but the mercenary and venal may be simply open to the bargain and sale which the hireling has already consummated; a clergyman may be mercenary in making place and pay of undue importance while not venal enough to forsake his own communion for another for any reward that could be offered him. — from venal
The mercenary may retain much show of independence; hireling service sacrifices self-respect as well as principle; a public officer who makes his office tributary to private speculation in which he is interested is mercenary; if he receives a stipulated recompense for administering his office at the behest of some leader, faction, corporation, or the like, he is both hireling and venal; if he gives essential advantages for pay, without subjecting himself to any direct domination, his course is venal, but not hireling. — from venal