English▸ noun [mass noun]
1 the practice of observing the requirements of law, morality, or ritual:
strict observance of the rules
the decline in religious observance.
▪ (observances) [count noun] an act performed for religious or ceremonial reasons:
official anniversary observances.
▪ [count noun] a rule to be followed by a religious order:
he drew up a body of monastic observances.
– ORIGIN Middle English: via Old French from Latin observantia, from observant- ‘watching, paying attention to’, from the verb observare (see observe).