[1] : The Collaborative International Dictionary of English v.0.48

observance \observ"ance\, n. f. observance, l. observantia.
   see observant.
   1. the act or practice of observing or noticing with
      attention; a heeding or keeping with care; performance; --
      usually with a sense of strictness and fidelity; as, the
      observance of the sabbath is general; the strict
      observance of duties.
      1913 webster

            it is a custom
            more honored in the breach than the observance.
                                                  --shak.
      1913 webster

   2. 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.
      1913 webster

            at dances
            these young folk kept their observances. --chaucer.
      1913 webster

            use all the observance of civility.   --shak.
      1913 webster

            some represent to themselves the whole of religion
            as consisting in a few easy observances. --rogers.
      1913 webster

            o i that wasted time to tend upon her,
            to compass her with sweet observances --tennyson.
      1913 webster

   3. servile attention; sycophancy. obs.
      1913 webster

            salads and flesh, such as their haste could get,
            served with observance.               --chapman.
      1913 webster

            this is not atheism,
            but court observance.                 --beau.  fl.
      1913 webster

   syn: observance, observation. these words are
        discriminated by the two distinct senses of observe. to
        observe means 1 to keep strictly; as, to observe a
        fast day, and hence, observance denotes the keeping or
        heeding with strictness; 2 to consider attentively, or
        to remark; and hence, observation denotes either the act
        of observing, or some remark made as the result thereof.
        we do not say the observation of sunday, though the word
        was formerly so used. the pharisees were curious in
        external observances; the astronomers are curious in
        celestial observations.
        1913 webster

              love rigid honesty,
              and strict observance of impartial laws.
                                                  --roscommon.
        1913 webster
see also:
observant observance observation 

[2] : WordNet (r) 2.0

observance
     n 1: the act of observing; taking a patient look syn: observation,
           watching
     2: a formal event performed on a special occasion; "a ceremony
        commemorating pearl harbor" syn: ceremony, ceremonial,
         ceremonial occasion
     3: the act of noticing or paying attention; "he escaped the
        notice of the police" syn: notice, observation
     4: conformity with law or custom or practice etc. syn: honoring
        ant: nonobservance
see also:
observation watching ceremony ceremonial ceremonial occasion notice 
honoring nonobservance 

[3] : Moby Thesaurus II by Grady Ward, 1.0

247 moby thesaurus words for "observance":
   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

Observance >> O Words
Observance, definition of term: Observance
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