I’m visiting area schools today, so there’s just time to define two words appearing in today’s Frank & Earnest comic strip.
Ka-ching - an imitation of the sound made by a cash register, according to
Mantra - taken from Hinduism, it is a “hymn or portion of text … chanted or intoned as an incantation or prayer,“ according to Webster’s
By the way, "ka-ching" is an example of onomatopoeia. That is when a word imitates a sound. Other examples include buzz and tinkle.