The American Heritage® Dictionary of the English Language: Fourth Edition. 2000.
Appendix I
Indo-European Roots
ENTRY:
sem-1
DEFINITION:
One; also adverbially as one, together with. Derivatives include simultaneous, hyphen, acolyte, and simple. I. Full-grade form *sem-.1a.hendecasyllabic, hendiadys, henotheism, hyphen, from Greek heis (< nominative singular masculine *hen-s < *hem-s), one; b. Greek he- in hekaton, one hundred (? dissimilated from *hem-katon; see dek). Both a and b from Greek *hem-.2. Suffixed form *sem-el-.simultaneous; assemble, ensemble, from Latin simul, at the same time. 3. Suffixed form *sem-golo-.single, from Latin singulus, alone, single. 4. Compound *sem-per- (*per, during, for; see per1). sempre; sempiternal, from Latin semper, always, ever (< once for all). II. O-grade form *som-.1.bonze, sambal, samhita, samsara, sandhi, Sankhya, sannyasi, Sanskrit, from Sanskrit sam, together. 2. Suffixed form *som-o-.a.same, from Old Norse samr, same, from Germanic *samaz, same; b. homeo-, homo-; anomalous, from Greek homos, same; c.homily, from Greek homlos, crowd. 3. Suffixed form *som-alo-.homolographic, from Greek homalos, like, even, level. III. Lengthened o-grade form *sm-.1. Suffixed form *sm-i-.seem, seemly, from Old Norse smr, fitting, agreeable (< making one, reconciling), from Germanic *smiz.2. Suffixed lengthened o-grade form *sm-o-.samizdat, samovar, from Russian sam(o)-, self. IV. Zero-grade form *s-.1.acolyte, anacoluthon, from Greek compound akolouthos, accompanying (-kolouthos, from o-grade of keleuthos, way, path), from ha-,a-, together. 2. Compound form *s-plo- (*-plo-, -fold; see pel-2). a.simple, from Latin simplus, simple; b.haploid, from Greek haploos,haplous, single, simple. 3. Suffixed form *sm-o-.a.some, from Old English sum, one, a certain one; b.some1, from Old English -sum, -like. Both a and b from Germanic *sumaz.4. Suffixed form *sm-alo-.similar; assimilate, resemble, from Latin similis, of the same kind, like. 5. Compound *s-kro-, of one growing (see ker-2). 6. Suffixed form *s-tero-. hetero-, from Greek heteros (earlier hateros), one of two, other. 7. Compound *s-plek-, one-fold, simple (*-plek-, -fold; see plek-). semplice, simplex, simplicity, from Latin simplex, simple. 8. Extended form *sma.hamadryad, from Greek hama, together with, at the same time. (Pokorny 2. sem- 902.)