thwart (adv.) [...] c. 1200, from a Scandinavian source, probably Old Norse þvert "across," originally neuter of thverr (adj.) "transverse, across," (cognate with Old English þweorh "transverse, perverse, angry, cross,")
from Proto-Germanic *thwerh- "twisted, oblique" (cognates: [...]),
altered (by influence of *thwer- "to turn") from *therkh-,
from PIE **terkw-* "to twist" (cognates: [...]), possibly a variant of *twerk- "to cut." From mid-13c. as an adjective.
This excellent helpful explanation and the above, describe the etymology to engage 'turns', rather than any 'twist', thus my question. This engagement of 'turns' is evidenced in the use of the word 'transverse' above, one of whose Latin etymons is vertere (= to turn).
Please expose and explain the hidden, missing semantic drifts and links. What is twisted?