soundness

As a noun soundness

is (uncountable) the state or quality of being sound.

As an adjective undefined is

lacking a definition or value.

As an adjective tenuous

is thin in substance or consistency.

As a noun soundness is

the state or quality of being sound.

As nouns the difference between heartiness and soundness

is that heartiness is the characteristic of being hearty; fillingness; wholesomeness while soundness is (uncountable) the state or quality of being sound.

As nouns the difference between robustness and soundness

is that robustness is the quality of being robust while soundness is (uncountable) the state or quality of being sound.

As a noun soundness

is (uncountable) the state or quality of being sound.

As an adjective unsound is

not sound; not whole; not solid; defective; infirm; diseased.

As nouns the difference between rationality and soundness

is that rationality is quality or state of being rational; agreement with reason; possession of reason; due exercise of reason; reasonableness while soundness is the state or quality of being sound.

Soundness is a synonym of strength.

As nouns the difference between soundness and strength

is that soundness is (uncountable) the state or quality of being sound while strength is the quality or degree of being strong.

As a verb strength is

(obsolete) to give strength to; to strengthen.

Soundness is a synonym of firmness.

As nouns the difference between soundness and firmness

is that soundness is (uncountable) the state or quality of being sound while firmness is the state of being firm; strength; permanence; stability; hardness; resolution.

Solidness is a related term of soundness.

As nouns the difference between solidness and soundness

is that solidness is the state or quality of being solid while soundness is (uncountable) the state or quality of being sound.

Soundness is a synonym of healthiness.

In uncountable|lang=en terms the difference between soundness and healthiness

is that soundness is (uncountable) the state or quality of being sound while healthiness is (uncountable) the state or quality of being healthy.

In countable|lang=en terms the difference between soundness and healthiness

is that soundness is (countable) the result or product of being sound while healthiness is (countable) the product or result of being healthy.

As nouns the difference between soundness and healthiness

is that soundness is (uncountable) the state or quality of being sound while healthiness is (uncountable) the state or quality of being healthy.