leg- / Indo-European roots
Examples of words with the root leg-: -logue, -logy, alexia, analects, analogous, anthology, apologue, apology, catalog, colleague, collect, Decalogue, delegate, dialect, diligent, dyslexia, eclectic, elect, epilogue, florilegium, homologous, horologe, intelligent, lectern, lectotype, lecture, leech, legacy, legal, legate.
To collect; with derivatives meaning "to speak." Oldest form *leg̑-, becoming *leg- in centum languages.
▲ Derivatives include leech1, lecture, legend, intelligent, sacrilege, loyal, logic.
1. Perhaps Germanic *lēkjaz, enchanter, one who speaks magic words. leech1 from Old English lǣce, physician.
2. lectern, lection, lecture, legend, legible, legion, lesson; coil1, collect1, diligent, elect, florilegium, intelligent, neglect, prelect, sacrilege, select, sortilege from Latin legere, to gather, choose, pluck, read.
3. lexicon, logion, -logue, -logy; alexia, analects, anthology, catalog, dialect, dialogue, dyslexia, eclectic, eclogite, eclogue, horologe, lectotype, prolegomenon from Greek legein, to gather, speak, with o-grade derivative logos, a gathering, speech (See also 6 below for derivatives independently built to logos).
4. Suffixed form *leg-no-. ligneous, ligni- from Latin lignum, wood, firewood (< "that which is gathered").
5. Possibly lengthened-grade form *lēg-.
a. legal, legist, legitimate, lex, loyal; legislator, privilege from Latin lēx, law (? < "collection of rules");
b. legacy, legate; colleague, collegial, delegate, relegate from Latin denominative lēgāre, to depute, commission, charge (< "to engage by contract"). (It is also possible, but uncertain, that Latin lēx comes, like English law from a form meaning "that which is set or laid down" from legh-).
6. Suffixed o-grade form *log-o-. logic, logistic, logo-, Logos, -logy; analogous, apologue, apology, Decalogue, epilogue, homologous, logarithm, paralogism, prologue, syllogism from Greek logos, speech, word, reason.
[Pokorny leg̑- 658.]