Timorous means to show nervousness or lack of confidence, most famously used in Rabbi Burns’ famous poem, to a mouse – ‘Wee Sleekit, couring, timorous beastie’

I chose the word because I heard it used in place of temerity, which means something quite different. Have temerity and wait till tommorrow to find exactly what!

Learn a new word every day.
Repeat it and remind yourself what it means at least three times in a day.
Try to use the word in conversation or writing today.
Get a dictionary and look words up.