The Latin pensare meant “to weigh”, in both senses: “to weigh something, such as gold, to get its value, usually to make a payment” or “to think about something deeply”.
From this word, we get a few Spanish words, including:
- Pensar — to “think”, just a simplification and lightening of the original.
- Pesadilla — with the diminutive ‑dilla ending added, it means “nightmare”. A dream is really just a small thought!
From the same Latin root, we get a few English words including:
- Pensive — with the same original meaning as the Latin.
- Compensate — which originally meant, “to counterbalance”, precisely what you do with a balance of justice!
- Pansy — which is basically an insult for someone who spends too much time thinking!
- Span — which originally meant to bind, and came from the original sense of weighing.
- Poise — originally meant, “to have a certain weight,” which then came to mean “to have a certain look”.
The p‑n-s root (sometimes without the ‘n’) is visible in all words.