conveniently (adv.)youdaoicibaDictYouDict
late 14c., "harmoniously," from convenient + -ly (2). Meaning "in a way that avoids difficulty" is from c. 1500.
desert (n.1)youdaoicibaDictYouDict
"wasteland," early 13c., from Old French desert (12c.) "desert, wilderness, wasteland; destruction, ruin," from Late Latin desertum (source of Italian diserto, Old Provençal dezert, Spanish desierto), literally "thing abandoned" (used in Vulgate to translate "wilderness"), noun use of neuter past participle of Latin deserere "forsake" (see desert (v.)).

Sense of "waterless, treeless region" was in Middle English and gradually became the main meaning. Commonly spelled desart in 18c., which is not etymological but at least avoids confusion with the other two senses of the word. Classical Latin indicated this idea with deserta, plural of desertus.
loner (n.)youdaoicibaDictYouDict
"one who avoids company," 1946; see lone. Apparently first in U.S. baseball slang (earliest reference is to Ted Williams).
Ted is likable enough in spite of his obsession with his specialty. He is something of a "loner," and he refuses to pal around with his teammates in off hours, but in the clubhouse he does his share of the talking. ["Life" magazine, Sept. 23, 1946]
pedo-youdaoicibaDictYouDict
before vowels ped-, word-forming element meaning "boy, child," from Greek pedo-, comb. form of pais "boy, child," especially a son, from PIE root *peu- "small, little, few, young" (see few (adj.)). The British form paed- is better because it avoids confusion with ped-.