英：metaphor; 法：metaphore
隐喻的通常定义是一种比喻，通过把某一事物比较于另一事物来对其加以描述，但并不直接点明其中的比较关系，这样的比喻便是隐喻。一个经典的例子即“朱丽叶是太阳”，在这一措辞中，莎士比亚通过把朱丽叶比作太阳来描述她那光彩照人的美丽，却没有使用“好像”一词来点明此种比较关系。
然而，拉康对该术语的使用很少归功于这则定义，而是更多归功于罗曼·雅各布森的著作。在发表于1956年的一篇重要的文章里，雅各布森在隐喻与换喻 (METONYMY)之间建立了一则对立。基于两种失语症之间的区分，雅各布森区分出了语言的两条基本对立的轴：隐喻轴涉及语言项目的选择且允许项目之间的替代，而换喻轴则涉及语言项目的组合（既有循序性又有同步性）。因而，隐喻便对应着索绪尔的纵向聚合 (paradigmatic)关系 (这些关系以“缺位”[in absentia]来维系)，而换喻则对应着横向组合 (syntagmatic)关系 (这些关系以“在场”[in praesentia]来维系)。
如同当时的很多其他法国知识分子 (诸如克劳德·列维-斯特劳斯与罗兰·巴特等人)一样，拉康也迅速采纳了雅各布森关于隐喻和换喻的重新解释。在雅各布森的奠基性论文得以发表的同一年里，拉康便在自己的研讨班上提到了这篇文章，并且开始将此一对立合并进他对弗洛伊德的语言学重读（见：S3,218-20,222-30)。一年之后，他又专门写了一整篇文章，以便更加详细地分析这则对立 (Lacan, 1957b)
雅各布森把隐喻等同于语言的替代轴，拉康据此把隐喻定义为一个能指对于另一能指的替代 (E, 164),并且提出了隐喻的第一公式 (E, 164: 图6)。
这则公式当做如下解读。在等式的左边，拉康在括号外面写下了fS, 表意功能（函数），也就是意指 (SIGNIFICATION)效果。在括号里面，拉康写下了S'/S, 表示“一个能指对于另一能指的替代”。在等式的右边，则有S, 表示能指，以及5，表示所指。介于这两个符号之间的符号 (+)则代表着对于索绪尔式算法中的那道杠 (BAR)（一）的穿越，并且代表着“意指的出现”。符号“≌”要读作“全等于”。因而，整个公式即读作：一个能指替代另一能指的表意功能全等于对杠的穿越。
在这则相当晦涩的公式化表达背后的思想，便是在语言中存在着一种针对意指的固有阻抗（这一阻抗是由索绪尔式算法中的那道杠来象征的）。意义并不完全是自发出现的，而是对杠进行穿越的一种特殊运作的产物。这则公式意在阐明拉康的以下论题，即拉康将其称作“意指”的此种运作，即意义的生产，只能通过隐喻而变得可能。隐喻因而是能指进入所指的通路，是一个新的所指的创造。
在写于几个月后的一篇文章里，拉康又提出了隐喻的另一公式 (E, 200; 图7)。
拉康自已对这则第二公式的说明如下：
那些大写的S即能指，x即未知的意指，而5则是由隐喻而导出的所指，这则隐喻由能指链条上的S对S'的替代而构成。S’的删除，在此由划在它上面的那道杠所代表，乃是隐喻成功的条件。
(E, 200)
拉康把他的隐喻概念放置在各种不同的语境下使用。
·俄狄浦斯情结拉康根据一则隐喻来分析俄狄浦斯情结，因为该情结涉及替代的关键概念，在此种情况下，是父亲的名义对于母亲的欲望的替代。这一基本隐喻，奠定了所有其他隐喻的可能性，被拉康命名为父性隐喻 (PATERNAL METAPHOR)。
·压抑 (REPRESSION)与神经症的症状拉康认为压抑（次级压抑）具有一种隐喻的结构。“换喻的对象”（即在先前的公式中被划消的能指S’)尽管遭到压抑，却会返回到由隐喻而产生的剩余意义 (+)之中。因此，压抑物的返回（即症状）也同样具有一种隐喻的结构；实际上，拉康断言说“症状即一则隐喻”（E, 175; 强调为原文所加）。
·凝缩拉康同样遵循雅各布森把隐喻一换喻的区分联系于弗洛伊德所描述的梦的工作的基本机制。然而，在此种类比的确切本质上，他又不同于雅各布森。对雅各布森而言，换喻同时联系着凝缩与移置，而隐喻则联系着认同与象征意义，但拉康则把隐喻联系于凝缩，而把换喻联系于移置 (见：Jakobson, 1956:258)。拉康继而指出，正如移置在逻辑上优先于凝缩，故而换喻是隐喻的条件。
·肛门冲动在弗洛伊德的《以肛欲为例论冲动的转化》一文中，他说明了肛欲何以会密切联系于替代的可能性一例如，粪便对于金钱的替代 (Freud, I917c)。拉康以此为基础把肛欲与隐喻联系了起来，“肛欲的水平即隐喻的地点一一个对象替代另一对象，给出粪便以替代阳具”(S11,104).
·认同 (DENTIFICATION)隐喻同样是认同的结构，因为认同即在于自身对他人的替代 (见：S3,218).
·爱 (L○VE)爱是像一则隐喻那样被结构的，因为它也涉及替代的运作。“正是就·有情人' (rastes)作为匮乏主体的功能来到了‘心上人' (eromenos)即所爱对象的位置上并且以自身替代了后者的功能而言，爱的意指才得以产生。”(S8,53)
(metaphore) Metaphor is usually defined as a trope in which one thing is described bycomparing it to another, but without directly asserting a comparison. A classic example isthe phrase 'Juliet is the sun', in which Shakespeare describes Juliet's radiant beauty bycomparing her to the sun, yet does not indicate this comparison by the use of the wordlike'.
However, Lacan's use of the term owes little to this definition and much to the workof Roman Jakobson, who, in a major article published in 1956, established an oppositionbetween metaphor and METONYMY. On the basis of a distinction between two kinds ofaphasia, Jakobson distinguished two fundamentally opposed axes of language: themetaphorical axis which deals with the selection of linguistic items and allows for theirsubstitution, and the metonymic axis which deals with the combination of linguistic items (both sequentially and simultaneously). Metaphor thus corresponds to Saussure'sparadigmatic relations (which hold in absentia) andmetonymy to syntagmaticrelationships (which hold in praesentia)(Jakobson, 1956).
Lacan, like many other French intellectuals of the time (such as Claude Levi-Straussand Roland Barthes), was quick to take up Jakobson's reinterpretation of metaphor andmetonymy. In the very same year that Jakobson's seminal article was published, Lacanrefers to it in his seminar and begins to incorporate the opposition into his linguisticrereading of Freud (see S3,218-20,222-30). A year later he dedicates a whole paper to amore detailed analysis of the opposition (Lacan, 1957b).
Following Jakobson's identification of metaphor with the substitutive axis oflanguage, Lacan defines metaphor as the substitution of one signifier for another (E, 164), and provides the first formula of metaphor (E, 164; Figure 8).
This formula is to be read as follows. On the lefthand side of the equation, outside thebrackets, Lacan writes f S, the signifying function, which is to say the effect ofSIGNIFICATION. Inside the brackets, he writes S'/S, which means 'the substitution ofone signifier for another'. On the righthand side of the equation there is S, the signifier, and s, the signified. Between these two symbols there is the symbol (+) which representsthe crossing of the BAR (-) of the Saussurean algorithm, and which represents 'theemergence of signification'. The sign =is
To be read: 'is congruent with'. Thus the whole formula reads: the signifying function ofthe substitution of one signifier for another is congruent with the crossing of the bar.
The idea behind this rather obscure formulation is that there is an inherent resistanceto signification in language (a resistance which is symbolised by the bar in the Saussurean algorithm). Meaning does not simply appear spontaneously, but is the productof a specific operation which crosses over the bar. The formula is meant to illustrate Lacan's thesis that this operation, the production of meaning, which Lacan calls'signification', is only made possible by metaphor. Metaphor is thus the passage of thesignifier into the signified, the creation of a new signified.
Lacan presents another formula for metaphor in a paper written a few months later (E, 200; Figure 9).
Lacan's own explanation of this second formula is as follows:
The capital Ss are signifiers, x the unknown signification and s thesignified induced by the metaphor, which consists in substitution in thesignifying chain of S for S'. The elision of S', represented here by the barthrough it, is the condition of the success of the metaphor.
(E, 200)
Lacan puts his concept of metaphor to use in a variety of contexts.
The Oedipus complex Lacan analyses the Oedipus complex in terms of a metaphorbecause it involves the crucial concept of substitution; in this case, the substitution of the Name-of-the-Father for the desire of the mother. This fundamental metaphor, whichfounds the possibility of all other metaphors, is designated by Lacan as the PATERNAL METAPHOR.
.REPRESSION and neurotic symptoms Lacan argues that repression (secondaryrepression) has the structure of a metaphor. The 'metonymic object' (the signifier whichis elided, S'in the previous formula) is repressed, but returns in the surplus meaning (+produced in the metaphor. The retumn of the repressed (the symptom) therefore also hasthe structure of a metaphor; indeed, Lacan asserts that 'the symptom is a metaphor' (E, 175, emphasis in original).
Condensation Lacan also follows Jakobson in linking the metaphor-metonymydistinction to the fundamental mechanisms of the dream work described by Freud However, he differs from Jakobson over the precise nature of this parallel. Whereas for Jakobson, metonymy is linked to both displacement and condensation, and metaphor toidentification and symbolism, Lacan links metaphor to condensation and metonymy todisplacement (see Jakobson, 1956:258). Lacan then argues that just as displacement islogically prior to condensation, so metonymy is the condition for metaphor.
The anal drive In his paper,'On transformations of instinct as exemplified in analeroticism', Freud shows how anal eroticism is closely connected with the possibility ofsubstitution-for example the substitution of faeces for money (Freud, 1917c). Lacantakes this as grounds for linking anal eroticism to metaphor;'The anal level is the locusof metaphor-one object for another, give the faeces in place of the phallus' (S11,104).
IDENTIFICATION Metaphor is also the structure of identification, since the latterconsists in substituting oneself for another (see S3,218).
.LOVE Love is structured like a metaphor since it involves the operation ofsubstitution.'It is insofar as the function of the erastes, of the lover, who is the subject oflack, comes in the place of, substitutes himself for, the function of the eromenos, theloved object, that the signification of love is produced' (S8,53).