undercurrent

noun

1. A current of water which flows under the surface, and often in a different direction from surface currents.

   “For that an undercurrent (which ſome have beleived,) in the ſtraights-mouth, will not ſolve this difficulty, unleſs occaſioned by a vaſt Gulf that muſt be placed ſomewhere in the Atlantic near the Mouth of the ſtraight, which though overflown and hidden by that mighty ſea, yet may poſſibly abſorb the deeper waters, and ſo cauſe a contrary undercurrent.”

   “[W]e have a surface current of saltish water from the poles towards the equator, and an undercurrent of water, saltier and heavier, from the equator to the poles. This undercurrent supplies in a great measure the salt which the upper current, freighted with fresh water from the clouds and rivers, carries back.”

2. (figuratively)A tendency of feeling or opinion that is concealed rather than exposed.

   “The meeting was pervaded with an undercurrent of dread, as the managers tried not to admit that firings were looming.”

   “All the while there was a busy undercurrent in her, like the thought of a man who keeps up a dialogue while he is considering how he can slip away.”

   “Voltaire showed little respect for any conventionality which did not command his acquiescence; yet it may be doubted whether an undercurrent of affectation does not more or less mar the effect of everything he has written.”

   “A vaguely defined genre (as the name announces, it was first noticed by the French), Film Noir is one of the more complex and intelligent Hollywood styles. Part detective story, part gangster, part urban melodrama, Film Noir was identified best by its dark and pessimistic undercurrents.”

   “Although the crowd was predominantly red-and-white, there was also a Romanian flavour, which these days in football terms tends to mean there is at least an undercurrent of discontent.”

verb

1. (also, figuratively, transitive)To flow under some surface.

   “The latter are stoically steady, impervious to the nervousness that still continues to undercurrent the Stock Exchange generally, despite an all-round rally.”

   “Her lips hardly moving, every feature steady, she undercurrented my narrative with ejaculations in French, Russian, Italian.”

   “The emotions undercurrenting the command left her with no doubt that he planned to do as he said.”

   “Mining-wights could be heard at work in the walls, sometimes undercurrented by the drone and whirr of eldritch spinning wheels.”