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easy: easy: [12] Easy comes via Anglo-Norman aise from Old French aisie, the past participle of aisier ‘put at ease’, which in turn was a derivative of aise. This noun (source of English ease [13]) originally meant ‘convenience’ rather than ‘comfort’. It came from *adjaces, the Vulgar Latin descendant of Latin adjacēns ‘nearby’ (source of English adjacent and related to adjective), which was the present participle of the verb adjacēre ‘lie near’.

The progression of senses is thus ‘nearby’, ‘handy’, ‘convenient’, and eventually ‘comfortable’. The subsequent development to ‘not difficult’, which took place in the 14th century, is purely English, although Breton took the parallel step of borrowing French aise, as aes, to mean ‘not difficult’.
=> adjacent, adjective
competence (n.): 1590s, "rivalry" (based on compete); c. 1600 "adequate supply;" 1630s, "sufficiency of means for living at ease," from French compétence, from Latin competentia "meeting together, agreement, symmetry," from competens, present participle of competere, especially in its earlier sense of "fall together, come together, be convenient or fitting" (see compete). Meaning "sufficiency to deal with what is at hand" is from 1790.
ease (n.): c. 1200, "physical comfort, undisturbed state of the body; tranquility, peace of mind," from Old French aise "comfort, pleasure, well-being; opportunity," which is of unknown origin, despite attempts to link it to various Latin verbs; perhaps Celtic. According to OED, the earliest senses in French appear to be 1. "elbow-room" (from an 11th century Hebrew-French glossary) and 2. "opportunity." This led Sophus Bugge to suggest an origin in Vulgar Latin asa, a shortened form of Latin ansa "handle," which could be used in the figurative sense of "opportunity, occasion," as well as being a possible synonym for "elbow," because Latin ansatus "furnished with handles" also was used to mean "having the arms akimbo." OED editors add, "This is not very satisfactory, but it does not appear that any equally plausible alternative has yet been proposed."

At ease "at rest, at peace, in comfort" is from late 14c.; as a military order (1802) the word denotes "freedom from stiffness or formality."
easy (adj.): c. 1200, "at ease, having ease, free from bodily discomfort and anxiety," from Old French aisie "comfortable, at ease, rich, well-off" (Modern French aisé), past participle of aisier "to put at ease," from aise (see ease (n.)). Sense of "not difficult, requiring no great labor or effort" is from late 13c.; of conditions, "offering comfort, pleasant," early 14c. Of persons, "lenient, kind, calm, gentle," late 14c. Meaning "readily yielding, not difficult of persuasion" is from 1610s. The concept of "not difficult" was expressed in Old English and early Middle English by eaþe (adv.), ieþe (adj.), apparently common West Germanic (compare German öde "empty, desolate," but of disputed origin.

Easy Street is from 1890. Easy money attested by 1889; to take it easy "relax" is from 1804 (be easy in same sense recorded from 1746); easy does it recorded by 1835. Easy rider (1912) was U.S. black slang for "sexually satisfying lover." The easy listening radio format is from 1961, defined by William Safire (in 1986) as, "the music of the 60's played in the 80's with the style of the 40's." Related: Easier; easiest.
life of Riley (n.): "life at ease," expression popularized by 1917, American English, sometimes said to trace to various songs from c. 1902.
otiose (adj.): 1794, "unfruitful, futile," from Latin otiosus "having leisure or ease,unoccupied, idle, not busy" (source of French oiseux, Spanish ocioso, Italian otioso), from otium "leisure, free time, freedom from business," of unknown origin. Meaning "at leisure, idle" is recorded from 1850. Compare Latin phrase otium cum dignitate "leisure with dignity." Earlier adjective in English was otious- "at ease" (1610s), and Middle English had noun otiosity (late 15c.).
romp (v.): 1709, "to play, sport, frolic;" 1734, "piece of lively play;" perhaps a variant of ramp (v.); but also see romp (n.). Meaning "to win (a contest) with great ease" first attested 1888. Related: Romped; romping.
scholar (n.): Old English scolere "student," from Medieval Latin scholaris, noun use of Late Latin scholaris "of a school," from Latin schola (see school (n.1)). Greek scholastes meant "one who lives at ease." The Medieval Latin word was widely borrowed (Old French escoler, French écolier, Old High German scuolari, German Schüler). The modern English word might be a Middle English reborrowing from French. Fowler points out that in British English it typically has been restricted to those who attend a school on a scholarship.
walk-over (n.): "easy victory," 1838, such as one that happens in the absence of competitors, when the solitary starter, being obliged to complete the event, can traverse the course at a walk. Transferred sense of "anything accomplished with great ease" is attested from 1902. To walk (all) over (someone) "treat with contempt" is from 1851.