Egg

The English word yolk (< OE geolca) is an allofam of yellow (< OE geolu) < PIE *ghel- ‘shine; shiny object’ [AHD:2029]. Similarly, TB words for YOLK typically contain a morpheme meaning YELLOW, e.g. Lahu g̈âʔ-u-ši ‘yolk of hen’s egg’ < #1606 PTB *k-rak FOWL / CHICKEN + #301 PTB *ʔu EGG / BIRD + ši ‘yellow/gold’ < #3496 PLB *s-rwəy¹ ⪤ *s-rwe¹ GOLD / YELLOW. See HPTB:191.

An important associated concept is BIRD, with several distinct roots appearing in compounds for EGG, including #1603 PTB *w(a/u) BIRD / EGG / WING / FOWL, #1600 PTB *haːr BIRD / FOWL / CHICKEN, #2187 PTB *b(y/r)a BIRD / BEE, #1604 PTB *daw BIRD, #3442 PTB *s-ŋak BIRD. It is sometimes hard to distinguish reflexes of *wa and *haːr; cf. the first syllable in Wancho ao-ti, below. Similarly, it is sometimes hard to distinguish reflexes of *wa and *bya; cf. the first syllable in Bahing ʔba-di.