For example, philosophy (along with the Greek root -soph- meaning "wisdom") is the study of human customs and the significance of life.
A philia is the love or obsession with a particular thing or subject.
Philias can be biological (e.g. rhizophilia, preference for living on roots) or chemical (e.g. chromophilous, materials that stain easily), or can be a hobby/liking (e.g. icthyophilia, love for fish).
However, English usage differs in some cases from the etymological use, and several of these words refer in English not to brotherly love but to sexual attraction.
Phil- (philo-) may also be used as a prefix with a similar meaning.