The routes follow a number of different grades of trail, as follows:
Road (Asphaltostromenos, Ασφαλτοστρωμενος)
Surfaced with concrete, asphalt, or tarmac. Signposted, and used by vehicles.
Dirt road (Chomatodhromos, Χωματοδρομος)
Bare rock, soil or dust road, used by vehicles, often bulldozed
Track (Pezodhromos, Πεζοδρομος)
Similar to dirt road, unsurfaced, but primarily not for vehicles.
Monopati (Μονοπατι, pl. monopatia) or kalderimi
Old mule road made of stones and often stepped and edged. Reliable, often leading to important places (settlements)
Path

Narrow way, not used by vehicles, may have gates or stiles, possibly overgrown. May be marked by cairns, paint spots, crosses or waymark signs.
Herders’ path
Often well-used, well-marked but may lead to pastures, herding area etc and not necessarily useful for walkers.
Goat path
Route created by livestock, therefore unreliable for walkers. Often patchy.
Freelance
I use the term 'freelance' when the route is not marked in any way. The final stages of a climb to a summit are often just taking a logical route over rising ground.
Note that Greeks usually refer to any route, regardless of condition, as 'dhromos, δρομος' (road) or 'οδος' (street) or 'stenos, στενος' (narrow street).
Cairn (soros lithon, σορος λιθων)
Paths are sometimes marked with heaps of stones called 'cairns'.
Col (dhiaselo, διασελο)
I use 'col' to mean the top of a pair of valleys, or the low point of a ridge.
Langadhi (λαγκαδι), rema (ρεμα) or farangi (φαραγγι)
A steep sided valley with or without water, i.e. gorge or ravine.
Plateau
Flat high ground.
Spur (antereisma, αντερεισμα)
A sloping ridge.
Summit pillar

Many hilltops have 1.5m high concrete triangulation pillars, which I call “summit pillar”.
Aloni (Αλονι)
Threshing floor, a circular paved area. With a low circumference wall, on a ridge above a settlement, often near a mill.
Chapel (Exoklisi Εξωκκλησι)

Small church, obviously, but without a kitchen or sleeping quarters.
Church (Ekklisia, Εκκλησια)

A larger, modern or restored place of worship, usually in towns.
Horio or Hora (χωριο, χωρα)
A village. The latter is more in the sense of the main town of the island, the former simply means village, but the two seem interchangeable.
House (spiti, σπιτι)
A common term, describing a wide range of dwellings. Larger detached houses in their own grounds are often called villas (βιλλα). Cottages, smaller houses in the country are kahlivi or kahliva (καλυβι). Farmhouses are agroikia (αγροικια).
Monastery

Encompasses wide range from the rural chapel(moni, μονι) with kitchen and sleeping quarters, used once a year for the festival, otherwise often deserted, through larger buildings (monastiri, μοναστηρι) possibly walled and fortified, to active, inhabited monasteries in the English sense.
Shrine (Eikonostasi, Εικονοστασι)
Small roadside structure, ranging from a tin or wooden box to elaborate models of churches in fenced enclosures. Contain oil lamps, candles, photos and mementos, commemorating a deceased person and often carrying a dedication to a saint.
In a country highly dependent on meagre water reserves, as you might expect there are many terms for water supplies, and the different features are well distinguished on Anavasi maps. If asking the way to a source of water, 'water','nero' (νερο) or 'nera' (νερα) will always do.
Cistern, sterna στερνα and dexameni δεχαμενι

All describe a tank for storing collected rainwater, often subterranean, sometimes constructed as the basement of a house. As the water is stagnant, sterilisation is necessary.
Potistiri or potistra ποτιστιρι, ποτιστιρα
A drinking-trough for animals.
Spring (anavlisi, αναβλυση or piyi, πηγη )

A natural water source, possible walled and tapped, in which case I describe it as a drinking fountain. In Greek, these are often just called taps (vrisi, βρυση). Spring water is safe to drink. The word krini, κρηνη is also used.
Well (pigadi, πιγαδι )
A subterranean water source, but may not be flowing, so I recommend sterilising water from one before use.