English

flob

Uncertain; possibly imitative.

A blend of phlegm + gob

Proto-Indo-European *bʰel- ‘to blaze, burn’

…

Ancient Greek φλέγμα ‘flame, fire, heat’

Latin phlegma

Old French fleume

Middle English flewme ‘Phlegm as one of the four cardinal humours…’

Transalpine Gaulish *gobbo- ‘neb, muzzle’

Old French gobet

Middle English gobbe

English gob

Today it means

noun Spittle or phlegm, especially a piece of spittle or phlegm that has been spat out.

Language periods are conventional ranges, not dates for this word.