Origins
The word 'collect' entered English in the early 15th century from Old French 'collecter' or directly from Latin 'collēctus,' the past participle of 'colligere' (to gather together). The Latin verb is a compound of 'com-' (together) and 'legere' (to gather, to pick, to choose, to read), from PIE *leǵ- (to gather, to collect). This PIE root is one of the most astonishingly productive in the entire Indo-European family, and understanding it illuminates a vast territory of the English vocabulary.
In Latin, 'legere' developed two primary senses: 'to gather/pick' and 'to read.' The connection between these seemingly different meanings is the physical act of picking out — just as one picks fruit from a tree, one picks out letters from a page. This is not a metaphor but a description of ancient reading practice: early Latin readers traced each letter individually, gathering them into syllables and words. The 'gathering' sense produced 'colligere' (to gather together → 'collect'), 'sēligere' (to pick apart → 'select'), 'ēligere' (to pick out → 'elect'), 'neglegere' (to not pick up → 'neglect'), and 'intellegere' (to choose between, to perceive → 'intelligent'). The 'reading' sense produced 'lēctiō' (a reading → 'lecture' and 'lesson'), 'legenda' (things to be read → 'legend'), and 'legibilis' (able to be read → 'legible').
In Greek, the same PIE root *leǵ- produced 'légein' (λέγειν), which meant 'to say, to speak, to tell' — another semantic development from 'gathering,' this time gathering words into speech. From 'légein' came 'lógos' (λόγος, word, reason, account — whence 'logic,' 'logos,' and every '-ology'), 'léxis' (speech, word — whence 'lexicon'), and 'dialégesthai' (to converse — whence 'dialogue' and 'dialect'). The legal sense also derives from this root: Latin 'lēx' (law, genitive 'lēgis') is from the same family, likely reflecting the idea of law as a 'collection' of rules or a 'reading out' of statutes. This gives us 'legal,' 'legislation,' 'legitimate,' and 'privilege' (literally 'private law' — 'prīvus' + 'lēx').
Latin Roots
The word 'college' is also a descendant of 'colligere.' Latin 'collēgium' (a society, a guild, a body of colleagues) derives from 'collēga' (one chosen together with another, a colleague — from 'com-' + 'legere' in the sense of 'to choose'). A college is, etymologically, a gathering of people chosen to work together. The word 'colleague' preserves this sense most directly.
The noun 'collect' (with stress on the first syllable: /ˈkɒl.ɛkt/) has a specialized meaning in liturgical English — a short prayer that 'collects' or gathers together the themes of a church service. This usage entered English from medieval Latin 'collēcta' (a gathering, and by extension the prayer said at the gathering), and it preserves the original Latin sense of bringing things together more faithfully than the verb does.
'Elegant' offers a particularly surprising connection. It comes from Latin 'ēlegāns' (tasteful, refined), from 'ēligere' (to pick out, to select — the same verb that gives us 'elect'). An elegant person or thing is one that has been 'picked out' or 'selected' — the implication being that elegance involves discriminating taste, the ability to choose well. So 'collect,' 'elect,' 'elegant,' and 'select' are all variations on the theme of picking, gathering, and choosing.
Proto-Indo-European Roots
The PIE root *leǵ- thus gave English an enormous vocabulary cluster spanning gathering (collect, select, elect), reading (lecture, legend, lesson, legible), speaking (logos, logic, dialogue), law (legal, legislation, privilege), institutions (college, colleague), and even aesthetics (elegant). Few roots have been so productive, and the thread connecting them all is remarkably simple: the act of picking things up and bringing them together, whether those things are objects, letters, words, ideas, laws, or people.