lukewarmness

haaleus

laimeus The property of being lukewarm; ambivalence, weakness.
1665, (w), New Experiments and Observations Touching Cold, Discourse II, in The Works of the Honourable Robert Boyle, London: A. Millar, 1744, Volume II, p. 246,http://catalog.hathitrust.org/Record/100900063

And indeed, there is scarce any quality, for whose differences we have fewer distinct names, having scarce any for the many degrees of coldness, that may be conceived to be intermediate, betwixt lukewarmness and the freezing degree of cold (..)

Mr. Hale was disappointed in his pupil’s lukewarmness about Greek literature, which had but a short time ago so great an interest for him.

Sazonov was furious at the lukewarmness of the British and French reactions to Russia's protests.