umgangssprachlich
https://dict.leo.org/pages/help/ende/abbrevia...

Hm, auf der Seite, die ich verlinkt habe, werden nur die englischen Abkürzungen erklärt...
ugs. = coll.

ugs. (umgangssprachlich) means that you can use it among family and friends, but not in a business letter.

I'm always a little confused about when to use "fam." (defined as "familiar" in English on Leo), "coll." or even "sl." when suggesting a new entry.

For example, in Leo, you have:

babe (Amer.) [coll.] das Schätzchen
toots [sl.] Schätzchen - familiäre Anrede
sweetie pie [fam.] Schätzchen
Dictionary: Schätzchen

or

scumbag [sl.] der Drecksack [ugs.]
scumbag [coll.] der Mistkerl
Dictionary: scumbag

Is "familiar" meant to be meaning 5. on Chambers: "5 over-friendly; excessively informal."? Or is it simply meant to mean "informal"?
And should we only use "slang" for very informal words, more informal than "colloquial" ones?
(Chambers: slang: 2 very informal words and phrases used by any class, profession or set of people. 3 language not accepted for dignified use. colloquial: a informal; b used in familiar conversation rather than in formal speech or writing.)