mainstay

As a noun mainstay

is a chief support.

As an adjective prominent is

standing out, or projecting; jutting; protuberant.

As nouns the difference between terms and mainstay

is that terms is while mainstay is a chief support.

As a noun mainstay

is a chief support.

As an adjective undefined is

lacking a definition or value.

As nouns the difference between anchor and mainstay

is that anchor is (label) a tool used to moor a vessel to the bottom of a sea or river to resist movement while mainstay is a chief support.

As a verb anchor

is to hold an object, especially a ship or a boat to a fixed point.

As nouns the difference between mainstay and mainstream

is that mainstay is a chief support while mainstream is that which is common; the norm.

As an adjective mainstream is

used or accepted broadly rather than by a tiny fraction of a population or market.

As a verb mainstream is

to educate (a disabled student) together with non-disabled students.

As nouns the difference between mainstay and mainspring

is that mainstay is a chief support while mainspring is the principal spring of a clockwork mechanism, that drives it by uncoiling.

As nouns the difference between mainstay and reliable

is that mainstay is a chief support while reliable is something or someone or dependable.

As an adjective reliable is

suitable]] or fit to be [[rely on|relied on; worthy of dependence or reliance; trustworthy.

is likely misspelled.

has no English definition.

As a noun mainstay

is a chief support.

As nouns the difference between mainstay and cornerstone

is that mainstay is a chief support while cornerstone is a ceremonial stone set at the corner of a building, joining two exterior walls, and often inscribed with the starting and completion dates of construction, the name of the architect and owner, and other details.

As nouns the difference between mainstay and buttress

is that mainstay is a chief support while buttress is a brick or stone structure built against another structure to support it.

As a verb buttress is

to support something physically with, or as if with, a prop or buttress.