No, because it is
n
ot a proper
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ou
n.
Yes, Siamese would be capitalized.
Yes, PC would be capitalized.
Some words need to be capitalized; others do not. For every word to be capitalized in a dictionary would be confusing because one would not know which words they would need to capitalize in everyday usage.
If you are talking about the caldera formed by a volcano collapsing then no it shouldn't be capitalized.
No, bookeeper would not be capitalized.
No, but if you named the purple amethyst Shelly, then it would be capitalized.
Based upon a Roman Legion's organization, it could be between 4800 and 5500. Many today would consider a legion to be roughly 6,000.
This can be determined if one divides it out, and 6000 goes into 100 60 times so there would be 60 centuries in a legion. (all depending on the actual unit type in the legion) a legion made up of only knights would be 60, but with regular foot soldiers the number would be significantly smaller.
Aquila ('the Eagle') was the name of a Roman legion's official standard that was carried into any battle that a legion would fight. It was important because a legion's soldiers considered it the symbol and the pride of their legion. Soldiers would fight to the death to protect their Eagle in battle and would consider losing it to the enemy a matter of great shame.
No, first frost would not be capitalized
Yes, it would be capitalized
His fans may be "legion" (a large group), but Beckham himself would be a legend.
No, colors are not typically capitalized unless they are part of a proper noun or title. For example, "red car" would not be capitalized, but "Red Cross" would be capitalized.
No it shouldn't be capitalized.
Yes, Siamese would be capitalized.
Yes, PC would be capitalized.
The Legion of Mary handbook, which you can access below list suggestions for activities, but I would assume that any such rule about collecting would be from an individual parish or diocese, not from the Legion.