汉：抽象名词后缀，表示状态、情况、性质、行为，-ance,-ancy二者同义，许多词具有-ance和-ancy两种形式后缀。
英：
-ance
word-forming element attached to verbs to form abstract nouns of process or fact (convergence from converge), or of state or quality (absence from absent); ultimately from Latin -antia and -entia, which depended on the vowel in the stem word. As Old French evolved from Latin, these were leveled to -ance, but later French borrowings from Latin (some of them subsequently passed to English) used the appropriate Latin form of the ending, as did words borrowed by English directly from Latin (diligence, absence). English thus inherited a confused mass of words from French and further confused it since c.1500 by restoring -ence selectively in some forms of these words to conform with Latin. Thus dependant, but independence, etc.
-ancy
word-forming element denoting quality or state, from Latin -antia, forming abstract nouns on pp. adjectives in -antem, appearing in English mostly in words borrowed directly from Latin (those passing through French usually have -ance or -ence; see -ance).
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-ance
a suffix used to form nouns either from adjectives in -ant or from verbs: brilliance; appearance.
Origin:
Middle English < Old French < Latin -antia -ancy, equivalent to -ant- -ant + -ia -y World English Dictionary
-ance or -ancy — suffix forming nouns
Compare -ence indicating an action, state or condition, or quality: hindrance ; tenancy ; resemblance
[via Old French from Latin -antia; see -ancy ]

-ancy or -ancy
— suffix forming nouns
[via Old French from Latin -antia; see -ancy ]
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1.abeyance
n.condition of not being in force or in use for a time 暂停，中止 *a(=to),bey(=gape)
例句：During the war,titles to private property were declared to be in abeyance.战争期间，私有财产权被宣布中止。
2.vigilance
n.watchfulness;keeping watch 警惕，警戒，警觉 * vigil(=lively)
例句：The President called for increased vigilance along the DMZ.总统要求加强非军事区域周边的警戒。
3.relevance
n.the condition of being closely connected with what is happening,being discussed,done,etc.关联；适当，适宜 *re(=again,intensive),lev(=lift,smooth)
例句：What relevance does this have to the matter at hand? 这和我们手头的问题有什么关系？
4.grievance
n.real or imagined cause for complaint or protest 抱怨，不满 *griev(heavy)
例句：Workers must file grievances through their union representative.工人要有不满通过工会申诉。
5.defiance
n. open disobedience or resistance,refusal to recognize authority,defying 反抗，蔑视；挑战 *de (=away,intensive).fi(d)(=trust)
例句：Defiance of the new rules will result in severe punishment.无视新规则将受到严厉惩罚。
6.allowance
n.sum of money,amount of something;deduction or discount;pocket money 限额；定量；折扣；零用钱 *al 例句：His weekly allowance was raised on his birthday.生日那天他每周的零用钱增加了。