A nonexhaustive list of senses which are much more specialized and idiosyncratic than the coarse-grained supersenses. They are also generally rare. (Perhaps we should call these "microsenses".)

See senses at The Preposition Project (TPP)

behind#

Operating/manning
  • behind the wheel; behind the counter

in#

Individual instantiating a role
  • You've got a friend in me
  • especially, someone serving an important role, such as a political candidate: "In Mehmet Oz, Herschel Walker and JD Vance, the Republican party has three celebrities running for Senate in November." (The Guardian)
  • person as a conduit for an action (used by no less an authority than the pope)
Musical key

for#

Causal discourse connective: old-fashioned
  • They stared, for they had never before seen such a creature.
?? TODO
(are these idiom-specific?)
  • can’t see the forest for the trees
  • not for want of trying

of#

Evaluee of degree-modified adjective
  • Is it really that good OF a restaurant?
  • They are too big OF a threat.
Property/part evaluee of non-degree-modified adjective
archaic-sounding
  • Cinderella’s stepsisters were beautiful OF face, but vile and black OF heart.
  • I am slow OF speech and slow OF tongue.

on#

Bearer of Responsibility
esp. financial responsibility
  • It's on you to make the case for the project.
  • Drinks are on me!
  • traveling on the taxpayer's dime
Drugs
  • I'm on heart medication
Progress
  • I'm on the third episode of the series.
Sustenance
sustaining fuel/resource
  • work on 3 hours’ sleep
  • running on an empty tank
  • making a decision on very little information
Target of opposition
arraying of literal or metaphorical force against some opponent. cf. TPP sense 11(5) OEC examples
  • [contest, e.g. fight or sport] man-on-man fight; cf. team1 takes on team2
  • [military/law enforcement] attack/assault on Pearl Harbor; war on drugs; firing on targets; "FBI moves on alleged members of extremist groups"; raid on bin Laden's compound
  • [advocacy] march on Washington

to#

Pseudopossessor
something that can be accessed with an associated instrument or part; or something with an associated quality
  • key to the door; entry to the room
  • There is a nice texture to the painting
Result infinitive
unexpected discovery prompted by a manner of gaining information (going somewhere, change of awareness)
  • I awoke/arrived (only) to find...

perhaps related to "suprised/disappointed to find..."

Toast
  • To health and prosperity!

with#

Adjective's cause
  • His hands were black with soot.
  • They listened to the inspirational speech, their eyes wet with tears.
  • I was numb with shock.

possessive: 's, `$, ...#

Superlative Object Construction