chuck
v.
1
"to throw," 1590s, variant of chock "give a blow under the chin" (1580s), possibly from French choquer "to shock, strike against," imitative (see shock, n.1). Related: Chucked; chucking.
n.
1
"piece of wood or meat," 1670s, probably a variant of chock, n. "block." "Chock and chuck appear to have been originally variants of the same word, which are now somewhat differentiated" [OED]. Specifically of shoulder meat from early 18c. American English chuck wagon (1880) is from the meat sense.
Chock and Chuck, Are low terms, very frequently used before full,--as the coach was chock full of passengers. The house was chuck full. [Daniel Powers, "A Grammar on an Entirely New System," West Brookfield, 1845]
2
"slight blow under the chin," 1610s, from chuck, v.1. Meaning "a toss, a throw" is from 1862. Related: Chucked; chucking.