The word humph in English dictionaries is usually defined as an interjection indicating annoyance, dissatisfaction, disgust or doubt. I am not sure that I have actually ever heard anyone pronouncing the word as it is spelt. It usually comes out as a kind of grunt or growl.
In Scots, the word humph might easily come accompanied by a series of grunts because it means to carry around something heavy. Before the days when suitcases came equipped with handy little wheels, humphing your luggage around airports or railway stations was an all too common part of the holiday experience.
But we still humph overflowing bags of shopping from supermarket to car and car to house unless we are going by bus or on foot, in which case the humphing process is likely to be accompanied by even more grunts. Also fond parents are obliged to humph around their small children when they claim to be too tired to walk. It is strange how the children do not seem to be quite so small after half a mile or so of this activity.
The verb humph can also mean to move around with great difficulty because you are carrying a heavy or unwieldy load. Thus you might see pupils from the local school humphin up the road clutching the many bags that some of them seem to need these day, while somehow still leaving a hand free to clutch their mobile phones.
In origin, humph is a Scots form of English hump, as in a curvature of the back. In Scots, English hunched becomes humphed and hunch-backed becomes humph-backed or humphie-backit. Humph has given rise to a number of phrases, but you have to know whether you are coming or going when you use some of them.
The phrase to come up yir humph means to occur to you, to come into your head, as in: “He might meet us off the train if it comes up his humph.” However, the phrase gae up yir humph means to be beyond your powers of understanding or to be a mystery to you, as in: “Why she left sae [so] suddenly gaes [goes] up ma humph.” If you set up yir hump you get very angry and hostile, as in: “He really sets up ma hump when he starts bragging.”
If you are tired of someone’s company and want to be rid of them, you can use the fairly modern informal expression awa an run up ma humph. This is certainly more picturesque than “Get lost”. Even more picturesque is awa and cuddle my humph.
There is another Scots word humph, with the alternative spelling humf, which is unrelated to the one just described. This one may be derived from the English interjection that I started off with. It means to have or acquire an offensive smell or taste, as of something decaying or rotting lying forgotten at the back of your fridge. Of course your fridge may be devoid of such remains.
If something is giving off a horrible smell it can be described as humphed or humphy. They are more or less synonyms for mingin, meaning stinking, but they have not acquired its popular figurative uses. Probably for this reason, humphy has not achieved the export success that mingin has. Still, you never know what a bit of publicity might do.