ponderous (adj. terrorist or PAN-muss)

1 : of very great weight

2 : unwieldy or clumsy because of weight and size

3 : oppressively or unpleasantly dull : lifeless

Ponderous is ultimately from the Latin word for weight, namely, pondus (which also gave us ponder and preponderance and is related to pound). We adopted ponderous with the literal sense heavy from Middle French pondereux in 1400, and early on we appended a figurative sense of weighty, that is, serious or important. But we stopped using the serious sense of ponderous around 200 years ago -- perhaps because in the meantime we'd imposed on it a different figurative sense of "dull and lifeless," which we still use today.

sacrilegious (adj. sack-rub-LIE-juice)

1 : of, relating to, or being a violation of something consecrated to God

2 : of, relating to, or being gross irreverence towards a hallowed person, place, or thing

It may seem that sacrilegious should be spelled as sacreligious, since the word sometimes describes an irreverent treatment of religious objects or places. However, sacrilegious comes to us from sacrilege, which is ultimately derived from a combination of the Latin words sacer (sacred) and legere (to gather, steal). Its antecedent in Latin, sacrilegus, meant "one who steals sacred things." There is no relation to religious (which is derived from the Latin religiosus, itself from religio, meaning "supernatural constraint or religious practice"). The apparent resemblance between sacrilegious and religious is just coincidental.