not 
/ˈnɑ:t/ adverb
/ˈnɑ:t/ adverb 1 a — used to form the negative of modal verbs (such as “should” and “could”) and auxiliary verbs (such as “do” and “have”) ▪ He would/could not stay. ▪ We have not spoken with them. ▪ It may not be fast, but it's reliable. ▪ That kind of behavior should not be allowed. ▪ He did not seem to care.
b — used before a verb or clause to make it negative or give it an opposite meaning ▪ They gave us the option of not attending. ▪ She told me not to do it. ▪ You are not to go there without permission. ▪ He seemed not to care. ▪ It's odd, but that's not to say [=that does not mean] that it's bad. — see also not to mention at 1mention 2 a — used with a word or phrase to make it negative or give it an opposite meaning ▪ The books are not here. ▪ No, that's not what I said. ▪ That's not funny! ▪ That is not necessarily true. ▪ You're not always right. ▪ You are not the only one who is worried. ▪ She is not (at all/very) pleased/happy. ▪ I'm not happy or sad, just bored. ▪ It is not as easy as it seems. ▪ Things are not going well. ▪ He is not guilty. ▪ He lives not far from here. ▪ “Are we there yet?” “Not quite.” ▪ “Is there any left?” “Not much.” ▪ It is not just/only/merely [=more than just] a novel; it is a literary classic. ▪ Not many [=few] people showed up. — see also not a few at 1few
b — used with a negative word to make a positive statement ▪ Their request is not unreasonable. [=their request is reasonable] ▪ His experience is not unusual. [=others have had similar experiences] ▪ “What do you think of the food?” “It's not bad.” [=it's pretty good]
c informal + humorous — used humorously at the end of a positive statement to show that you really meant the opposite ▪ That's very interesting—not! [=that's not interesting] 3 : less or fewer than
▪ He was standing not six feet away from me. ▪ The bullet passed not five inches from my head! ▪ Not all of us agree. [=some of us do not agree] ▪ Not everybody finds her work interesting. [=some people find her work boring] 4 — used to refer to a possible situation, condition, etc., that is different from or opposite to another situation, condition, etc. ▪ The planet is sometimes hard to see and sometimes not. [=and sometimes easy to see] ▪ It works in theory if not in practice. [=even if it doesn't work in practice] — often used in the phrase or not ▪ Believe it or not [=whether you believe me or don't believe me], we were there just last week. ▪ Ready or not, here I come! ▪ Like it or not, you'll do as he says. [=you'll do as he says whether you like or don't like it] 5 — used to give a negative answer to a question ▪ “Do you think they forgot?” “I hope not.” ▪ “Should we go?” “I'd rather not.” ▪ “Do you think it's true?” “Probably/Certainly not.” ▪ “Do you mind?” “Not at all.”
b — used before a verb or clause to make it negative or give it an opposite meaning ▪ They gave us the option of not attending. ▪ She told me not to do it. ▪ You are not to go there without permission. ▪ He seemed not to care. ▪ It's odd, but that's not to say [=that does not mean] that it's bad. — see also not to mention at 1mention
b — used with a negative word to make a positive statement ▪ Their request is not unreasonable. [=their request is reasonable] ▪ His experience is not unusual. [=others have had similar experiences] ▪ “What do you think of the food?” “It's not bad.” [=it's pretty good]
c informal + humorous — used humorously at the end of a positive statement to show that you really meant the opposite ▪ That's very interesting—not! [=that's not interesting]
▪ He was standing not six feet away from me. ▪ The bullet passed not five inches from my head! ▪ Not all of us agree. [=some of us do not agree] ▪ Not everybody finds her work interesting. [=some people find her work boring]
more often than not
: happening more than half the time
▪ He wins more often than not. [=he wins more than he loses] ▪ More often than not, I stay home instead of going out.
▪ He wins more often than not. [=he wins more than he loses] ▪ More often than not, I stay home instead of going out.
not a/one
: no thing or person
▪ There was not one available taxi to be found. [=no taxis were available] ▪ Not a/one single person showed up. [=no one showed up] ▪ Not a word came out of her mouth.
▪ There was not one available taxi to be found. [=no taxis were available] ▪ Not a/one single person showed up. [=no one showed up] ▪ Not a word came out of her mouth.
not that
— used to say that something said before is not important ▪ I tried to help, not that it mattered. [=but it did not matter] ▪ I saw him with some other woman, not that I care. [=but I don't care]
