Proto-Dyke 

Usually found in pairs, proto-dykes are a pair of female friends (usually teenagers) who are so close, their friendship verges on being a lesbian relationship, but in most cases without any sexual element.

In most cases, these girls will grow up to be completely heterosexual (though some will become lesbian or bisexual)

Did you see Helen and Jane back there? They such proto-dykes, they're practically lesbians.

Proto-Dyke by Twisted Smile April 28, 2010