In military terms the difference between train and staff

is that train is the men and vehicles following an army, which carry artillery and other equipment for battle or siege while staff is an establishment of officers in various departments attached to an army, to a section of an army, or to the commander of an army. The general's staff consists of those officers about his person who are employed in carrying his commands into execution.

In transitive terms the difference between train and staff

is that train is to move (a gun) laterally so that it points in a different direction while staff is to supply (a business) with employees.

As nouns the difference between train and staff

is that train is elongated portion while staff is a long, straight stick, especially one used to assist in walking.

As verbs the difference between train and staff

is that train is to practice an ability while staff is to supply (a business) with employees.

Assertion is a related term of protestation.

As nouns the difference between assertion and protestation

is that assertion is the act of asserting, or that which is asserted; positive declaration or averment; affirmation; statement asserted; position advanced while protestation is a formal solemn objection or other declaration.

Reverberation is a related term of knell.

As nouns the difference between reverberation and knell

is that reverberation is reverberation while knell is the sound of a bell knelling; a toll.

As a verb knell is

to ring a bell slowly, especially for a funeral; to toll.

Heartrending is a related term of rueful.

As adjectives the difference between heartrending and rueful

is that heartrending is that causes great grief, anguish or distress while rueful is causing, feeling, or expressing regret or sorrow.

Association is a synonym of relations.

As nouns the difference between association and relations

is that association is the act of associating while relations is .

Straightforward is a related term of abrupt.

As adjectives the difference between straightforward and abrupt

is that straightforward is proceeding in a straight course or manner; not deviating; honest; frank while abrupt is (obsolete|rare) broken away (from restraint) .

As an adverb straightforward

is in a straightforward manner.

As a verb abrupt is

(archaic) to tear off or asunder .

As a noun abrupt is

(poetic) something which is ; an abyss .

Desire is a related term of gusto.

As verbs the difference between desire and gusto

is that desire is while gusto is .

Fearful is a related term of sinister.

As adjectives the difference between fearful and sinister

is that fearful is frightening while sinister is inauspicious]], ominous, unlucky, illegitimate (as in [[w:bar sinister|bar sinister ).

As adjectives the difference between unattached and unjoined

is that unattached is not married or involved in a romantic relationship while unjoined is not joined.

As a verb unjoined is

past tense of unjoin.

Intricate is a related term of mixed.

As adjectives the difference between intricate and mixed

is that intricate is having a great deal of fine detail or complexity while mixed is having two or more separate aspects.

As verbs the difference between intricate and mixed

is that intricate is to become enmeshed or entangled while mixed is (mix).