Dictionary.com
se·ren·i·ty
/səˈrɛnɪti/ Show Spelled[suh-ren-i-tee] Show IPA
–noun, plural -ties for 2.
1.
the state or quality of being serene, calm, or tranquil; sereneness.
2.
( usually initial capital letter ) a title of honor, respect, or reverence, used in speaking of or to certain members of royalty (usually prec. by his, your, etc.).
se·rene
/səˈrin/ Show Spelled[suh-reen] Show IPA
–adjective
1.
calm, peaceful, or tranquil; unruffled: a serene landscape; serene old age.
2.
clear; fair: serene weather.
3.
( usually initial capital letter ) most high or august (used as a royal epithet, usually prec. by his, your, etc.): His Serene Highness.
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Personal definition: a state of peace