Increase is a synonym of expansion.

As nouns the difference between expansion and increase

is that expansion is the act or process of expanding while increase is an amount by which a quantity is increased.

As a verb increase is

to become larger.

Convincing is a related term of unimpeachable.

As adjectives the difference between convincing and unimpeachable

is that convincing is effective as proof or evidence while unimpeachable is not able to be impeached or reproached.

As a verb convincing

is .

As nouns the difference between duct and trough

is that duct is a pipe, tube or canal which carries gas or liquid from one place to another while trough is a long, narrow container, open on top, for feeding or watering animals.

As verbs the difference between duct and trough

is that duct is to channel something through a duct (or series of ducts while trough is to eat in a vulgar style, as if eating from a trough.

As nouns the difference between relationship and familiarity

is that relationship is connection or association; the condition of being related while familiarity is the state of being extremely friendly; intimacy.

Acuity is a related term of competence.

As nouns the difference between acuity and competence

is that acuity is sharpness or acuteness, as of a needle, wit, etc while competence is skill.

Acquiescence is a related term of sanction.

As nouns the difference between acquiescence and sanction

is that acquiescence is a silent or passive assent or submission, or a submission with apparent content; - distinguished from avowed consent on the one hand, and on the other, from opposition or open discontent; quiet satisfaction while sanction is an approval, by an authority, generally one that makes something valid.

As a verb sanction is

to ratify; to make valid.

In transitive terms the difference between hew and slash

is that hew is to shape; to form while slash is to reduce sharply.

As a conjunction slash is

Used to connect two or more identities in a list.