Carefull

Part of speech: adjective, adverb

Definitions

1. Showing caution and watchfulness to prevent harm or mistakes ; done with close attention to accuracy and thoroughness
2. Mindful and prudent about avoiding danger or damage ; marked by precision and meticulous attention to every detail
3. Taking pains to stay safe and avoid trouble ; executed with painstaking thoroughness and a concern for getting things right

Etymology: The spelling "carefull" is an obsolete form of "careful", a word that has been in English since Old English, when it appeared as "carful". Its origin is plain: it combines "care", which goes back to the Old English "caru" meaning sorrow, grief or anxiety, with the suffix "-ful", meaning full of. A careful person was once simply full of care, weighed down by worry, before the sense shifted toward attentiveness and watchfulness. The double "l" in "carefull" came from the way "-ful" was often written in earlier English, when the suffix was spelled "full" even though it was pronounced as a weakened syllable. Writers kept that spelling for centuries, and the doubled form is simply a historical variant of the same word.