v.1. To pronounce something slowly and carefully: The student practiced sounding out the English vowels. I sounded the phrase out until I could say it correctly.
2. To pronounce the letters of some word slowly and in sequence in order to arrive at the pronunciation or meaning of the whole: If you don't know the word, try to sound it out. I tried to sound out the word, but its spelling didn't match its pronunciation.
3. To examine or investigate the opinion or nature of someone or something: The company conducted a survey to sound out public opinion. I tried to sound them out before asking for the favor so that I wouldn't put them in an awkward position.
4. To project a sound: The bell sounded out at midnight.