The American Heritage® Dictionary of the English Language: Fourth Edition. 2000.
Appendix I
Indo-European Roots
ENTRY:
dh(i)-
DEFINITION:
To suck. Contracted from *dhe1(i)-. Derivatives include female, fawn2, fetus, fennel, and affiliate. 1. Suffixed reduced form *dh-mn-.female, feme, feminine; effeminate, from Latin fmina, woman (< she who suckles). 2. Suffixed reduced form *dh-to-.fawn2, fetal, fetus; effete, feticide, superfetate, from Latin ftus, pregnancy, childbearing, offspring, with adjective ftus,fta, pregnant. 3. Suffixed reduced form *dh-kwondo-.fecund, from Latin fcundus, fruitful. 4. Suffixed reduced form *dh-no-.fennel, finochio; fenugreek, sainfoin, from Latin fnum,faenum, hay (< produce). 5. Probably suffixed zero-grade form *dh-lyo- (< *dhi-lyo-). filial, filiate, fils1; affiliate, hidalgo, from Latin flius, son, and flia, daughter (but these are conceivably from the root bheu-). 6. Suffixed reduced form *dh-lo-.fellatio, from Latin flre,fellre, to suck. 7. Suffixed reduced form *dh-l-k-.felicitate, felicity; felicific, infelicity, from Latin flx, fruitful, fertile, lucky, happy. 8. Suffixed reduced form *dh-l-.endothelium, epithelium, mesothelium, from Greek thl, nipple. 9. Suffixed reduced form *dh-l-u-.theelin, from Greek thlus, female. (Pokorny dh(i)- 241.)