Valid is a related term of moral.

As an adjective valid

is valid.

As a noun moral is

moral.

Unavailing is a related term of unsatisfactory.

As adjectives the difference between unavailing and unsatisfactory

is that unavailing is useless, fruitless, futile while unsatisfactory is inadequate, substandard or not satisfactory.

Essential is a related term of notable.

As adjectives the difference between essential and notable

is that essential is necessary while notable is (obsolete) useful; profitable or notable can be worthy of notice; remarkable; memorable; noted or distinguished.

As nouns the difference between essential and notable

is that essential is a necessary ingredient while notable is a person or thing of distinction.

As nouns the difference between doctrine and position

is that doctrine is a belief or tenet, especially about philosophical or theological matters while position is a place or location.

As a verb position is

to put into place.

Dull is a synonym of unimaginative.

As adjectives the difference between dull and unimaginative

is that dull is lacking the ability to cut easily; not sharp while unimaginative is not imaginative.

As a verb dull

is to render dull; to remove or blunt an edge or something that was sharp.

As adjectives the difference between disgusting and irksome

is that disgusting is causing disgust; repulsive; distasteful while irksome is disagreeable or troublesome by reason of long continuance or repetition; bothersome; annoying; irritating; wearisome; tedious.

As a verb disgusting

is present participle of lang=en.

As adjectives the difference between biting and afflictive

is that biting is causing a stinging sensation while afflictive is that causes physical or mental pain.

As a verb biting

is present participle of lang=en.

As a noun biting

is the action of the verb to bite.

Unstable is a related term of wandering.

As adjectives the difference between unstable and wandering

is that unstable is having a strong tendency to change while wandering is which wanders; travelling from place to place.

As a noun wandering is

travelling with no preset route; roaming.

As a verb wandering is

.

Preeminent is a related term of august.

As an adjective preeminent

is pre-eminent.

As a proper noun august is

the eighth month of the gregorian calendar, following july and preceding september abbreviation: aug' or ' or august can be .

As adjectives the difference between ancient and customary

is that ancient is having lasted from a remote period; having been of long duration; of great age; very old while customary is agreeing with, or established by, custom; established by common usage; conventional; habitual.

As nouns the difference between ancient and customary

is that ancient is a person who is very old while customary is a book containing laws and usages, or customs; a custumal.