1. (n.) The act noticing with special attention; a heeding or keeping with care; as, the observance of the Sabbath\ is general; the strict observance of duties.

2. (n.) An act, ceremony, or rite, as of worship or respect; especially, a customary act or service of attention; a form; a practice; a rite; a custom.

3. (n.) Servile attention; sycophancy.

accommodation accord accordance acquiescence adaptation adaption adherence adhering adjustment adoration advertence advertency agreement alertness allegiance anniversaries assiduity assiduousness attention attention span attentiveness awareness baccalaureate service bon ton care carrying out celebrating celebration ceremonial ceremony churchgoing cognizance commemoration commencement completion compliance complying concentration conformance conformation other-direction conforming conformity congruity consciousness consideration consistency consuetude convention conventionality convocation correspondence cultism custodianship custody custom devotedness devotion devoutness diligence discharge dressing ship duteousness dutifulness duty eagle eye ear earnestness effectuation empty formality enforcement espial espionage established way etiquette examination execution exercise exercises faith faithfulness fanfare fanfaronade fashion fealty festivity flexibility flourish of trumpets folkway form form of worship formal formality formula formulary fulfillment function graduation graduation exercises guard guardedness guardianship habit harmony heed heedfulness heeding holiday holy rite homage inaugural inauguration initiation inspection institution intentiveness intentness invigilation jubilee keeping line liturgy looking lookout love of God loyalty malleability manner manners mark marking the occasion memorialization memory mind mindfulness mode of worship monitoring mores mummery mystery note notice obedience obediency obeying observation observing office order of worship ordinance orthodoxy ovation peeled eye performance pietism piety piousness pliancy practice praxis prescribed form prescription proctoring proper thing prosecution prudence qui vive recognition reconcilement reconciliation regard regardfulness rejoicing religion religionism religious ceremony religious rites religiousness remark remembrance respect respecting revel reverence rite rite de passage rite of passage ritual ritual observance rituality sacrament sacramental salute salvo scrutiny service servility servitium sharp eye social convention solemn observance solemnity solemnization spying standard behavior standard usage standing custom stewardship strictness submission submissiveness suit and service suit service surveillance testimonial testimonial banquet testimonial dinner theism thought time-honored practice toast tradition traditionalism transaction tribute triumph uniformity usage use veneration viewing vigil vigilance wariness watch watch and ward watchful eye watchfulness watching way weather eye what is done willingness witnessing wont wonting worship worshipfulness