The expression to be a bore had been used in print in the sense of "to be tiresome or dull" since 1768 at the latest.[4] The expression "boredom" means "state of being bored," 1852, from bore (v.1) + -dom. It also has been employed in a sense "bores as a class" (1883) and "practice of being a bore" (1864, a sense properly belonging to boreism, 1833).[5] The word "bore" as a noun meaning a "thing which causes ennui or annoyance" is attested to since 1778; "of persons by 1812". The noun "bore" comes from the verb "bore", which had the meaning "[to] be tiresome or dull" first attested [in] 1768, a vogue word c. 1780–81 according to Grose (1785); possibly a figurative extension of "to move forward slowly and persistently, as a [hole-] boring tool does."[6]
“Time is quixotic because it can torment us. When we have insufficient stimulus to fill our lives, we resent the relentless quality of time, and we engage in activities designed to “kill time.” Time that passes slowly creates insufferable boredom; time that passes to quickly makes us aware of our accelerated death march. A person’s perspective on time depends mostly on what they are most afraid of, boredom or death.”
In Experience Without Qualities: Boredom and Modernity, Elizabeth Goodstein traces the modern discourse on boredom through literary, philosophical, and sociological texts to find that as "a discursively articulated phenomenon...boredom is at once objective and subjective, emotion and intellectualization—not just a response to the modern world but also a historically constituted strategy for coping with its discontents."[3] In both conceptions, boredom has to do fundamentally with an experience of time and problems of meaning.
Second, boredom typically occurs when people have trouble focusing their attention and they believe the reason for this difficulty is in the environment. When sitting in the airport, for example, there is probably a lot going on. There are people having conversations that you could listen to. You probably have something to read. There may be televisions showing the news. But, the stress of waiting for a delayed flight often makes it hard to concentrate, and so your mind jumps from one thing to another. You assume that this is caused by the environment, and so you feel boredom.

“To me, at least in retrospect, the really interesting question is why dullness proves to be such a powerful impediment to attention. Why we recoil from the dull. Maybe it’s because dullness is intrinsically painful; maybe that’s where phrases like ‘deadly dull’ or ‘excruciatingly dull’ come from. But there might be more to it. Maybe dullness is associated with psychic pain because something that’s dull or opaque fails to provide enough stimulation to distract people from some other, deeper type of pain that is always there, if only in an ambient, low-level way, and which most of us spend nearly all our time and energy trying to distract ourselves from feeling, or at least from feeling directly or with our full attention. Admittedly, the whole thing’s pretty confusing, and hard to talk about abstractly…but surely something must lie behind not just Muzak in dull or tedious places any more but now also actual TV in waiting rooms, supermarkets’ checkouts, airport gates, SUVs’ backseats. Walkman, iPods, BlackBerries, cell phones that attach to your head. This terror of silence with nothing diverting to do. I can’t think anyone really believes that today’s so-called ‘information society’ is just about information. Everyone knows it’s about something else, way down.”
Boredom also has its benefits. It is important to see boredom as a “call to action” (Svendsen, 1999). Nietzsche suggested that men of rare sensibility value boredom as an impetus to achievement. Boredom can be a catalyst for action. It can provide an opportunity for thought and reflection. It can also be a sign that a task is a waste of time—and thus not worth continuing.
One more key element of boredom is control. Boredom often occurs when you have little control over your situation. Waiting rooms, lectures, and airline gates are all places where you have little control over your situation. Normally, we react to unpleasant situations by changing the situation. If you don’t like a book you are reading, for example, you close it and do something else. Boredom happens when you are unable to change the situation.  

The most common way to define boredom in Western culture is having nothing to do. Boredom is generally viewed as an unpleasant emotional state in which the individual feels a pervasive lack of interest in and difficulty concentrating on the current activity. The condition corresponds more precisely to the French ennui, an existential perception of life’s futility. Ennui is a consequence of unfulfilled aspirations (Goodstein, 2005).