"Awesome" is a word that is used in modern speech but that has old and solemn origins. It first showed up in print in the late 1500s and early 1600s to mean "showing awe" or "deeply reverent." It soon gained the weightier sense "causing a feeling of awe" and was used in more formal and serious settings for about 400 years. Then, in the 1960s, it began to pick up the "terrific" sense we hear today as an extension of the "causing awe" sense. Today, we associate the word "awesome" with lighthearted informal use.