I googled Intimacy...

Wiki's explanation is pretty impressive.

Intimate refers generally to the innermost nature or fundamental character of something. Intimacy refers to a familiar and very close connection with another as a result of entering deeply or closely into relationship through knowledge and experience of the other.

Genuine intimacy in human relationships requires dialogue, transparency, vulnerability and reciprocity. As a verb "intimate" means "to state or make known". The activity of intimating (making known) underpins the meanings of "intimate" when used as a noun and adjective. As a noun, an "intimate" is a person with whom we have a particularly close relationship. This was clarified by Dalton (1959) who discusses how anthropologists and ethnographic researchers access 'inside information' from within a particular cultural setting by establishing networks of intimates capable (and willing) to provide information unobtainable through formal channels.

As an adjective, "intimate" indicates detailed knowledge of a thing or person (e.g. "an intimate knowledge of engineering" and "an intimate relationship between two people".

In human relationships, the meaning and level of intimacy varies within and between relationships. In anthropological research, intimacy is considered the product of a successful seduction, a process of rapport building that enables parties to confidently disclose previously hidden thoughts and feelings. Intimate conversations become the basis for 'confidences' (secret knowledge) that bind people together.

Developing an intimate relationship typically takes a considerable amount of time (months and years, rather than days or weeks) and both anthropologists and zoologists have tracked the subliminal changes in body language as rapport develops between two or more people.

To sustain intimacy for any length of time requires well developed emotional and interpersonal awareness. Intimacy requires an ability to be both separate and together participants in an intimate relationship. This is called self-differentiation. It results in a connection in which there is an emotional range involving both robust conflict, and intense loyalty. Lacking the ability to differentiate one self from the other is a form of symbiosis, a state that is different from intimacy, even if feelings of closeness are similar.

From a centre of self knowledge and self differentiation intimate behaviour joins family, close friends as well as those with whom one is in love. It evolves through reciprocal self-disclosure and candour. Poor skills in developing of intimacy can lead to getting too close too quickly; struggling to find the boundary and to sustain connection; being poorly skilled as a friend, rejecting self-disclosure or even rejecting friendships and those who have them.

Scholars distinguish between different forms of intimacy, principally: emotional intimacy and physical intimacy. Emotional intimacy, particularly in sexual relationships, typically develops after physical bonds have been established. 'Falling in love', however, has both a biochemical dimension, driven through reactions in the body stimulated by sexual attraction (PEA, and a social dimension driven by 'talk' that follows from regular physical closeness and/or sexual union.

It is worth distinguishing intimate (communal) relationships from strategic (exchange) relationships. Physical intimacy occurs in the latter but it is governed by a higher order strategy, of which the other person may not be aware. For example getting close to someone in order to get something from them or give them something. That 'something' might not be offered so freely if it did not appear to be an intimate exchange and if the ultimate strategy had been visible at the outset. Mills and Clark (1982) found that strategic (exchange) relationships are fragile and easily break down when there is any level of disagreement. Emotionally intimate (communal) realtionships are much more robust and can survive considerable (and even ongoing) disagreements.

In new relationships, sexual intimacy may develop slowly and in a predictable way. Research by Desmond Morris, a behavioral psychologist, found that most new relationships followed 12 predictable steps on the path to sexual intimacy. Couples that rushed through the steps or skipped steps were most likely to break up. The 12 steps he identified (in order) are: Eye to Body, Eye to Eye, Voice to Voice, Hand to Hand, Arm to Shoulder, Arm to Waist, Mouth to Mouth, Hand to Head, Hand to Body, Mouth to Breast, Hand to Genitals, and finally, Sexual Intercourse.
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