Is "Many thanks" a proper usage? | many thanks
AsMarthasays,manythanksisperfectlyidiomatic.However,itisindeedanoddlyisolatedidiom:mostotherconstructionswhichtrytotreatthanksasapluralnounareungrammatical(eg*lotsofthanks),andthere’scertainlynosuchthingas*athank.Inthesenseof“feelingsofgratitude”itcanbeusedeitherasamassnoun(thanksisduetoGodforthisharvest…),oraplural(thanksareduetoGod…).Inthesenseof“expressionsofgratitude”,itcanbeusedaseitherofthese,oralsoasasingular:aspecialthanksisduetothechairman…[Sourcesforthis:roughlycountinghitsforphras...
As Martha says, many thanks is perfectly idiomatic. However, it is indeed an oddly isolated idiom: most other constructions which try to treat thanks as a plural noun are ungrammatical (eg *lots of thanks), and there’s certainly no such thing as *a thank.
In the sense of “feelings of gratitude” it can be used either as a mass noun (thanks is due to God for this harvest…), or a plural (thanks are due to God…). In the sense of “expressions of gratitude”, it can be used as either of these, or also as a singular: a special thanks is due to the chairman…
[Sources for this: roughly counting hits for phrasings like thanks is, thanks are in Google and COHA[1].]
How did it get this way? The entries for thanks in the OED tell a tangled tale, but as far as I can make out, thank was originally an acceptable singular noun (their last citation is 1642, Is this the thanke which you returne to God?), but the plural form thanks gradually predominated, and apparently lost ...