The difference between Proboscis and Trunk

Proboscis as a noun (anatomy):

An elongated tube from the head or connected to the mouth, of an animal. The tubular feeding and sucking organ of certain invertebrates like insects, worms and molluscs. The trunk of an elephant.

Proboscis as a noun (informal, mildly, jocular):

A large or lengthy human nose.

Trunk as a noun (biological):

Part of a body. The usually single, more or less upright part of a tree, between the roots and the branches: the tree trunk. The torso. The conspicuously extended, mobile, nose-like organ of an animal such as a sengi, a tapir or especially an elephant. The trunks of various kinds of animals might be adapted to probing and sniffing, as in the sengis, or be partly prehensile, as in the tapir, or be a versatile prehensile organ for manipulation, feeding, drinking and fighting as in the elephant.

Trunk as a noun:

A container. A large suitcase, chest, or similar receptacle for carrying or storing personal possessions, usually with a hinged, often domed lid, and handles at each end, so that generally it takes two persons to carry a full trunk. A box or chest usually covered with leather, metal, or cloth, or sometimes made of leather, hide, or metal, for holding or transporting clothes or other goods. The luggage storage compartment of a sedan/saloon style car; a boot

Trunk as a noun:

A channel for flow of some kind. A circuit between telephone switchboards or other switching equipment. A chute or conduit, or a watertight shaft connecting two or more decks. A long, large box, pipe, or conductor, made of plank or metal plates, for various uses, as for conveying air to a mine or to a furnace, water to a mill, grain to an elevator, etc. A long tube through which pellets of clay, peas, etc., are driven by the force of the breath. A peashooter A flume or sluice in which ores are separated from the slimes in which they are contained.

Trunk as a noun (software engineering):

In software projects under source control: the most current source tree, from which the latest unstable builds (so-called "trunk builds") are compiled.

Trunk as a noun (transport):

The main line or body of anything. A main line in a river, canal, railroad, or highway system. The part of a pilaster between the base and capital, corresponding to the shaft of a column.

Trunk as a noun:

A large pipe forming the piston rod of a steam engine, of sufficient diameter to allow one end of the connecting rod to be attached to the crank, and the other end to pass within the pipe directly to the piston, thus making the engine more compact.

Trunk as a noun:

Shorts used for swimming (swim trunks).

Trunk as a verb (obsolete):

To lop off; to curtail; to truncate.

Trunk as a verb (mining):

To extract (ores) from the slimes in which they are contained, by means of a trunk.