perturb

verb

1. (transitive)To cause (something) to be physically disordered or disturbed; to cause confusion.

   “Mary therefore the more knaue art thou I ſay / That perturbeſt the worde of god I ſay […]”

   “The Nobles ſtandyng by hearyng him thus ſpeake were greatly agreeued with him, notyng in him arrogancy and wilfulneſſe, in perturbyng and refuſyng ſuch an honeſt order of agreement: […]”

   “[T]he grounds and firſt inventions of Poeticall fables, […] vvere alſo taken up by hiſtoricall VVriters, perturbing the Chaldean and Ægyptian Records vvith fabulous additions, and confounding their names and ſtories, vvith their ovvne inventions.”

   “If it [benign matter] be as yet ſeated in the Lymph, and ſcarce got in among the Globules, it vvill notvvithſtanding provoke, and perturb the vital Spirits, and ſo exagitate them as to ſtir up an Efferveſcence, vvhich ceaſeth again as ſoon as the Matter can be concocted and throvvn out by inſenſible Tranſpiration, Svveat, Urine, Stools, &c.”

   “[T]hou perturbest my place; / Takest from me the country of my forefathers; […]”

2. (transitive)To disturb (someone, their mind, etc.) mentally; to bother, trouble, upset.

   “[…] I have often found / The truth thereof, in my private paſſions: / For I doe never feele my ſelfe perturb'd / VVith any generall vvords 'gainſt my profeſſion, / They doe avvake, and ſtirre me: […]”

   “He remembered how, […] his childish imagination was perturbed at a phenomenon, for which he could not account.”

   “[I]t is very easy to abstain from this sin [the desire of money]. For here it is not any natural desire that perturbeth the mind, but it ariseth from wilful negligence.”

   “"Did he seem to you much perturbed?" / "Mr. Gibson is a very strong, self-contained man. I do not think that he would ever show his emotions on the surface. But I, who knew him so well, could see that he was deeply concerned."”

3. (transitive)Of a celestial body: to modify the motion or orbit of (another celestial body) by exerting a gravitational force; hence (physics), to slightly modify (the motion of an object).
4. (transitive)To slightly modify (a set of equations or their solutions), producing deviations from a simple, easily solvable problem, in order to find an approximate solution to a problem that is more difficult to solve or otherwise unsolvable.
5. (transitive)To influence (a process or system) so that it deviates from its normal state.
6. (intransitive)To bother, to disturb, to trouble.

   “Thy ghoſt O father ſweete, thy greuous ghoſt, / Perturbing in my dremes hath me compeld to ſee this coaſt.”

   “This growth original of virgin soil, / By fascination felt in opposites, / Pleases and shocks, entices and perturbs.”