botulismyoudaoicibaDictYouDict
botulism: [19] The fact that Latin botulus was used metaphorically for ‘intestine’ is in this case just a red herring; its principal meaning was ‘sausage’, and it was the discovery of the foodpoisoning germ in cooked meats, such assausages, which led to the term botulism. Early work on unmasking the bacterium responsible (now known as Clostridium botulinum) was done in Germany, and at first the German form of the word, botulismus, was used in English, but by the late 1880s we find the naturalized botulism fairly well established.
mask (v.)youdaoicibaDictYouDict
1560s, "take part in a masquerade;" 1570s, "to disguise;" 1580s, "to wear a mask," from mask (n.). Figurative use by 1580s. Extended sense of "to disguise" is attested from 1847. Related: Masked; masking. Masking tape recorded from 1927; so called because it is used to block out certain surfaces before painting.
Scotch (adj.)youdaoicibaDictYouDict
"of Scotland," 1590s, contraction of Scottish. Disdained by the Scottish because of the many insulting and pejorative formations made from it by the English (such as Scotch greys "lice;" Scotch attorney, a Jamaica term from 1864 for strangler vines).

Scotch-Irish is from 1744 (adj.); 1789 (n.); more properly Scots-Irish (1966), from Scots (mid-14c.), the older adjective, which is from Scottis, the northern variant of Scottish. Scots (adj.) was used in Scottish until 18c., then Scotch became vernacular, but in mid-19c. there was a reaction against it. Scotch Tape was said to be so called because at first it had adhesive only on the edges (to make it easier to remove as a masking tape in car paint jobs), which was interpreted as a sign of cheapness on the part of the manufacturers.
unmask (v.)youdaoicibaDictYouDict
1580s in figurative sense, c. 1600 in literal sense (transitive and intransitive), from un- (2) "reverse, opposite of" + mask (v.). Related: Unmasked; unmasking.