Intimacy generally refers to being in a close personal association with another. It is a familiar and very close affective connection with someone as a result of a bond that is formed through knowledge and experience of the other.

Genuine intimacy in human relationships requires dialogue, transparency, vulnerability, and reciprocity.

The 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. The noun "intimate" means a person with whom one has a particularly close relationship. The adjective "intimate" indicates detailed knowledge of a thing or person.

In human relationships, the meaning and level of intimacy varies within and between relationships.

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. Murray Bowen called this "self-differentiation". It results in a connection in which there is an emotional range involving both robust conflict and intense loyalty.

From a center of self-knowledge and self differentiation, intimate behavior joins family members and close friends as well as those in love. It evolves through reciprocal self-disclosure and candor. Poor skills in developing 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.

Studies show that fear of intimacy is inversely related to comfort with emotional closeness and with relationship satisfaction, and directly related to loneliness and trait anxiety.

[From Wikipedia]