The kumquat is a mysterious subject
Kumquats or cumquats are a group of small fruit-bearing trees in the flowering plant family Rutaceae, either forming the genus Fortunella, or placed within Citrus sensu lato. The edible fruit closely resembles that of the orange (Citrus sinensis), but it is much smaller and ovular, being approximately the size and shape of a large olive. The English name "kumquat" derives from the Cantonese pronunciation gam1 gwat1 (given in Jyutping romanization).
Neither tasty nor delicious (as opposed to topkek) these small fruit still leave their mark on /s4s/. Despite numerous efforts, kumquat is still spelled with a 'k'.