When attached to some words, refers to a love of, or deep affection for something, someone.
From the Greek term 'philia' which means love, affection but not necessarily in a sexual or erotic sense. More of a friendship love, a brotherly/sisterly love.
The Greeks used other words, for sexual love, affection, though today, in English, the word does carry sexual connotations with it.
Eros was the most noted term in Greek, referring to sexual love, sexual romance.
Example being the entire list of Paraphilias, which is considered by Psychologists to refer to include all sexual disorders.
Modern English contradicts the original meaning, in claiming that some words have no sexual connotations, while others do.
Necrophilia is the love of (sexual attraction, arousal) a corpse.
While Retrophilia is a love of things from the past.
One is considered a Paraphilia, the other not.
Practice (Associated Acts):
In some instances, such as under Biology, the term can be used to denote conditions, illnesses, and/or diseases.
Hemophilia for example, is a blood disease.
Hellenophile on the other hand is someone who has a love for the Greek Culture.
Phil or Philo can also be used, as a prefix, with similar meanings to the suffix uses of the word.
Philately for example, is the love of stamps while Philanderer is someone of questionable sexual morals. A love of sex?
There are five major areas where this suffix (prefix version) is used.
Sexology, Biology, Chemistry/Physics, Hobbies, and to Nation, or affinity to Nations.
These endings, are opposite to those ending in 'phobia' which is an aversion, dislike, fear.