on thin ice vs safe

on thin ice

prep
  • In a dangerous, hazardous, or delicate situation; at risk. 

adv
  • dangerously, hazardously, delicately 

safe

verb
  • To make something safe. 

adj
  • Great, cool, awesome, respectable; a term of approbation, often as interjection. 

  • Lenient, usually describing a teacher that is easy-going. 

  • In a location that renders it difficult to hit with the cue ball. 

  • Reliable; trusty. 

  • When a batter successfully reaches first base, or when a baserunner successfully advances to the next base or returns to the base he last occupied; not out. 

  • Not in danger; out of harm's reach. 

  • Cautious. 

  • Providing protection from danger; providing shelter. 

  • Free from risk. 

  • Of a programming language, type-safe or more generally offering well-defined behavior despite programming errors. 

  • Properly secured. 

  • Not susceptible to a specified source of harm. 

noun
  • A condom. 

  • A box, usually made of metal, in which valuables can be locked for safekeeping. 

How often have the words on thin ice and safe occurred in a corpus of books? (source: Google Ngram Viewer )