In conversations people often use "not bad". How to interpret this?
Are they feeling good or just not bad or somewhere in the middle?
Does it depend on the context?
E.g.:
X: How are you doing today?
Y: Not bad. You?
Does "not bad" mean "good"?
E.g.:
X: How was the food in that new restaurant?
Y: Not bad.
Are there examples showing "not bad" doesn't mean "good" either?
It's common in English to use these types of statements where a direct answer might seem too assertive. For example, if you'd asked me how I had been lately, I might say "not bad", rather than "good", as being good implies being better than normal, whereas not bad is just not bad.
In fact, people often describe things in terms of them not being the opposite of what they are. Other examples include:
English speakers often avoid making assertive statements unless they fully intend to be assertive. For example, they may begin a statement of fact with "I believe...", "It seems..." or "Apparently...".
Using direct assertions sparingly gives them more impact too. To say "He's stupid" is less forgiving than saying "He's not the brightest chap I've ever met."
Edwin Ashworth noted in his comment that this amelioration is known as hedging, and the not un-X form described in this answer is known as litotes. From Wikipedia:
In rhetoric, litotes is a figure of speech and form of verbal irony in which understatement is used to emphasize a point by stating a negative to further affirm a positive, often incorporating double negatives for effect.
It depends on where you are usually.
In the USA it typically means "average" or OK. The food wasn't bad, but it wasn't good either.
In the UK it typically means "good". We don't tend to be very encouraging so if there is a food I like and someone asks how it tastes, my response is usually "Not bad. I really like it"
Northern British for good/great. “Not bad” is used to acknowledge things could be a lot worse without giving away that everything is actually fine. There’s an element of machismo mixed with a touch of cynicism. Culturally the phrase does not translate much further south than the Mersey/Humber line in Britain. “Nay bad” and “no bad” are alternative forms found in Scotland and Ireland, whilst “Not bad” and “Not so bad” are more common in Northern England.
In response to the question “How are you?”, “not bad” means “I acknowledge your greeting and I am providing the socially accepted response.”
If I’m feeling particularly effusive I might say “Not bad. You?” To which you might respond “Can’t complain.” A wise person woul leave it at that but I might say “No one listens if you do”, thus completing the ritual, thereby releasing the elder gods who will justifiably damn my soul for all eternity.
That’s because “How are you?” and its variants are not questions even though they look like questions. They’re greetings like hello, hi, g’day, morning etc. That makes “not bad” and its variants responses, not answers. They’re formulaic; they dont mean anything.
At the risk of generlisation, British English tends towards understatement so “not bad” is the most common formula. American English tends towards overstatement so “good” or even “great” might be more common. Notwithstanding, each is equally devoid of meaning.
In response to a genuine inquiry, such as when your doctor at a consultation asks “How are you?”, “not bad” can mean anything from really, really terrible to absolutely fantastic depending on context and tone.
For example, in response to “How’s the pain?”, “not bad” is context dependent: in response to a paper cut it means trivial, in response to a broken leg it means awful but I’m coping with it, and in response to an obviously fatal injury it means really, really awful but I’ll be dead soon so there’s that to look forward to.
Similarly, tone can make all the difference. Said with enthusiasm and vim “not bad” can mean “great”; said morosely it can mean “I have clinical depression”, and said sarcastically it can mean “you’re a bloody idiot.” Without any particular inflection it usually means “not bad”.
Its a very versatile phrase.
In conversations people often use "not bad". How to interpret this?
Does it depend on the context?
Yes, and to a lesser extent on intonation. I have bolded a couple of the passages in an extract from following article that addresses (amongst other phrases) "Not bad".
The article concerns British English, but there is overlap with American English. It is entitled "Euphemistically Speaking" appeared in May 2011 in The Economist. It's worth reading.
A FRIEND of mine was recently told by his boss that his position at work was "unassailable": in British office-speak that is a severe warning which has sent him hastily looking for a new job.
It reminded me of a guide I came across a few years ago, which aimed to help plain-speaking Dutch executives make sense of their English colleagues.
What the British say: "I hear what you say"
What the British mean: "I disagree and do not want to discuss it any further"
What is understood: "He accepts my point of view"
What the British say: "With the greatest respect"
What the British mean: "I think you are wrong (or a fool)"
What is understood: "He is listening to me"
What the British say: "That's not bad"
What the British mean: "That's good or very good"
What is understood: "That's poor or mediocre"
You will note the following in which the emphasis alters the meaning:
What the British say: "QUITE good" (with the stress on the "quite")
What the British mean: "A bit disappointing"
What is understood: "Quite good"
What the British say: "quite GOOD" (with the stress on the "good ")
What the British mean: "excellent"
What is understood: "Quite good"
Likewise, said with a genuine smile, or any indication of happiness, "Not bad" = excellent. Said with a degree of hesitancy = (generally) Awful, appalling, unacceptable; (health) Near death; very ill, in pain; etc.
A few more:
What the British say: "I was a bit disappointed that/It is a pity you..."
What the British mean: "I am most upset and cross"
What is understood: "It doesn't really matter"
What the British say: "Very interesting"
What the British mean: "I don't agree/I don't believe you"
What is understood: "They are impressed"
What the British say: "That is an original point of view"
What the British mean: "You must be mad, or very silly"
What is understood: "They like my ideas!"
