Pronunciation: [θˈiːvɪʃli] (IPA) 
The correct spelling of the word "thievishly" may initially confuse some due to its combination of letters. However, the word is phonetically spelled as /ˈθiːvɪʃli/ which helps to break down the pronunciation. The th sound and the ee sound make up the "thi" part while the "v" and "ish" sounds make up the middle section. Finally, the "ly" at the end denotes that it is an adverb, making the overall meaning "in a thievish manner".
Thievishly is an adverb derived from the term "thievish". The term refers to the characteristics, actions, or behaviors related to or resembling a thief or thievery. It describes the act of behaving in a sneaky, dishonest, or illicit manner with intentions of taking someone else's property or belongings without permission or through deceit.
A person who acts thievishly tends to exhibit cunning and deceitful behavior, often engaging in secret or furtive actions to gain personal advantage or gratification at the expense of others. They are inclined to engage in illegal or dishonest activities, such as theft, burglary, or embezzlement. Thievishly may also be associated with a deceitful or fraudulent nature, as individuals acting in this manner may manipulate or deceive others to achieve their objectives or gain undeserved advantages.
Furthermore, thievishly can be used to describe actions that are marked by a lack of integrity, honesty, or ethical standards. It signifies an inclination to engage in actions that violate trust or exploit vulnerabilities to obtain personal gain. In a broader metaphorical sense, it can also be used to describe actions that are calculated and devious, aiming to obtain an unfair advantage or exploit loopholes for personal benefit.
In summary, thievishly pertains to actions, behaviors, or characteristics that resemble or relate to thievery, involving deceitfulness, cunning, dishonesty, or illegal activities to acquire someone else's property or gain an unwarranted advantage.
The state or quality of being thievish.
Etymological and pronouncing dictionary of the English language. By Stormonth, James, Phelp, P. H. Published 1874.
The word "thievishly" is derived from the root word "thievish", which in turn comes from the noun "thief".
The noun "thief" can be traced back to the Old English word "theof", which is derived from the Proto-Germanic word "*theubaz". This Proto-Germanic word likely originated from the Proto-Indo-European root "*teup-", meaning "to sneak" or "to steal".
Over time, the Old English "theof" transformed into "thief", and in Middle English, the suffix "-ish" was added to form "thievish". The suffix "-ish" is used to create adjectives and often indicates a quality or resemblance to the base word.
