Mostrar (Spanish for “to show”) comes from the Latin root, monstrare (“to point out”), which comes from monstrum, an “omen from God; a wonder.”
From that root monstrum, we get two related English words:
- Demonstrate — A demonstration, after all, is just a showing!
- Monster — A monster was originally a messenger from God. But just a bad one!
We can see how the m-n-st-r root in the original Latin was preserved in the two English descendants but turned into m-st-r in the Spanish mostrar, losing the middle -n-.
It’s curious how the sense of awe and wonder, of a God-given message, has been lost as monstrum — the divine omen! — turned into mere demonstrations or just showings, mostrar. Sounds like the modern world, in a nutshell.