Nouns

(n)confidant, intimatesomeone to whom private matters are confided

Verbs

(v)intimate, adumbrate, insinuategive to understand“I insinuated that I did not like his wife”
(v)suggest, intimateimply as a possibility“The evidence suggests a need for more clarification”

Adjectives

(s)intimatemarked by close acquaintance, association, or familiarity“intimate friend”, “intimate relations between economics, politics, and legal principles” (V.L. Parrington)
(s)private, intimateconcerning things deeply private and personal“intimate correspondence”, “private family matters”
(s)cozy, intimate, informal, cosyhaving or fostering a warm or friendly and informal atmosphere“had a cozy chat”, “a relaxed informal manner”, “an intimate cocktail lounge”, “the small room was cozy and intimate”
(s)familiar, intimatehaving mutual interests or affections; of established friendship“on familiar terms”, “pretending she is on an intimate footing with those she slanders”
(s)intimateused euphemistically to refer to the genitals“he touched her intimate parts”
(s)intimate, sexualinvolved in a sexual relationship“the intimate (or sexual) relations between husband and wife”, “she had been intimate with many men”
(s)inner, internal, intimateinnermost or essential“the inner logic of Cubism”, “the internal contradictions of the theory”, “the intimate structure of matter”
(s)intimate, knowledgeable, versedthoroughly acquainted through study or experience“this girl, so intimate with nature” (W.H.Hudson), “knowledgeable about the technique of painting” (Herbert Read)