Geophyte

Geophyte [ Botany ]		Dictionary of botanic terminology index of names
Adjective: Geophytic

Herbaceous perennial plant with underground storage organs and perennating bud (s) buried below the soil level which form aerial growth.

(Photo 1) Haworthia emelyae v. comptoniana.
The tuberose roots of this succulent geophyte are Contractile and pull the plant deeper into the soil to protect the perennating bud from sun and heat during the dry season.

Geophytes are a kind of plant having the capability to survive arid environmental conditions by dying back to underground storage organs. Storage organs are reserves of food (e.g. carbohydrates, proteins), nutrients (e.g. mineral salt), and water, and may be classified as bulbs, corms, rhizomes, stem tubers, root tubers, and enlarged hypocotyls (caudex).
This phase in geophyte development is often referred to as a dor mancy period or resting stage; however, such terms are misleading. The storage organ is never physiologically dormant even when aerial growth is halted. It continues to change and constantly senses its environment so the term "dormancy" will more properly refers to the period of the geophyte life cycle when there is no above-ground tissue.
The above ground portions of the plant (usually annual deciduous shoots or leaves) typically die off during the dry parts of the year or in the winter season leaving only the storage organs in the soil, but the plant is able to "re"-sprout when the environmental conditions are appropriate using the food reserves in the underground portion and as a result, geophytes in their natural habitats are capable of perennial life cycles.
Most geophytic plant species may be propagated by division or proliferation of the underground structure such as a bulbs, rhizomes, tubers,.

Geophytes are a subdivision of cryptophytes plant

Cryptophytes:
Plants with resting buds lying either beneath the surface of the ground as a bulbs, corms, rhizomes, etc., or a resting buds submerged under water.

Cryptophytes are further divided up into one of the following:

Geophytes: resting in dry land, e.g. Tulip, Ariocarpus
Helophytes: resting in marshy, lake or pond edges, e.g. Reed Mace.
Hydrophytes: resting by being submerged under water, e.g. Frogbit.

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Holdfast roots [ Botany ]
Dictionary of botanic terminology - index of names

Some species of climbing plants develop holdfast roots which help to support the vines on trees, walls, and rocks. By forcing their way into minute pores and crevices, they hold the plant firmly in place.

Climbing plants, like the poison ivy (Toxicodendron radicans), Boston ivy (Parthenocissus tricuspidata), and trumpet creeper (Campsis radicans), develop holdfast roots which help to support the vines on trees, walls, and rocks. By forcing their way into minute pores and crevices, they hold the plant firmly in place. Usually the Holdfast roots die at the end of the first season, but in some species they are perennial. In the tropics some of the large climbing plants have hold-fast roots by which they attach themselves, and long, cord-like roots that extend downward through the air and may lengthen and branch for several years until they strike the soil and become absorbent roots.

Major references and further lectures:
1) E. N. Transeau “General Botany” Discovery Publishing House, 1994