【Bond】 , 【band】 , 【tie】 all denote something which serves to bind or bring two or more things firmly together, but they differ from each other not only in implications but in their specific applications.

【Bond】 often retains its basic implication of restraint upon the freedom of the individual.

It may be applied to a restraining device (as a rope, a chain, a fetter, or a manacle) which prevents a prisoner from escaping or, more broadly, to something that interferes with one′s liberty and holds one down.

But  【bond】 is equally applicable to something that connects or brings together two individuals (persons or things) or all the individuals comprising a group or mass into a stable union. In this sense the term may and often does refer to a connection that is primarily spiritual; occasionally, especially when the plural is used, there is also a hint of restraint or constraint.

【Band】 (see also STRIP) may imply, like 【bond】 , a restraint, a fastening, or a connection, but it more usually also implies something material in the form of a flat and narrow piece of material, often one that forms a hoop or ring; thus, a 【band】 around the hair is worn to confine the hair and may be a ribbon with ends tied together or a hoop or half hoop (as of metal or plastic); an endless strip of rubber or elastic material is called a rubber 【band】 ; a hooplike piece which holds together two parts of a structure (as the barrel and stock of a gun or two sections of a pillar) is called a 【band】 ; also, a straight member of a wall (as continuous molding, a frieze, or a strip of brickwork in a different pattern) often serves not only as an ornament but also as a union or connection between two sections of the wall or structure, and is therefore called in architecture a 【band】 .

【Tie】 basically applies to a 【bond】 or 【band】 for fastening or restraining which is of a flexible substance (as rope, cord, or string) and can be secured by knotting the loose ends together or one end to the thing fastened and the other to its support. Consequently, in extended use, 【tie】 tends to suggest a less integral union and often more flexibility in the connection than  【bond】 , which it otherwise closely resembles; thus, one breaks the 【bond】 of friendship but one severs the 【tie】 of friendship; the ties of blood suggest the pull exerted by blood relationship, but the 【bond】 of blood suggests an obligation or a duty.

【Tie】 , as applied to specific fastenings or connections, is used chiefly when the object of the connection is not (as in 【bond】 ) to form into an integral unit or (as in 【band】 ) to keep closely united or together but to bring together two things that are affected by common forces so that when they are subjected to strain or tension they will not spread or pull apart; thus, the transverse bars on which rails rest and which serve to keep the rails equidistant from each other are called ties; a piece (as a beam, a post, or a rod) which connects two parts or sides of a structure (as the ribs of a vessel or the two sides of a pointed arch) and serves to brace and stay the whole is called a 【tie】 .