Hapax

Dal Dizionario della Lingua Italiana Devoto – Oli edizione 2000-2001:

hapax <hà·pax /’a-/> (anche hapax legomenon, pl. hapax legomena) s.m. parola o espressione di cui è documentato un solo esempio: un hapax oraziano, dantesco. [Dalla loc. gr. hápax legómenon, 'detto una volta sola'].

Dawdle

Da Your Dictionary.com:

dawdle intransitive verb, transitive verb to waste (time) in trifling or by being slow; idle: often with away.

Usage examples: As long as you’re sensible and cautious you shouldn’t get robbed; just don’t dawdle when you take your nightly strolls.
I could dawdle about in the nursery and count the apricots on the wall.
So what if they dawdle along at 28 in a 30?

Synonyms: loaf, idle, lounge; loiter.

Etymology: < ? or akin to ME dadel(ing), chattering (of birds), dadelar, glib talker, probably of echoic origin.