high, senior, superior, top, upper
middle
inferior, junior, low
the lowest ranks of the army

first, second
He is in the first rank of designers.

social
Cabinet, ministerial (BrE)
a politician of Cabinet rank

achieve, attain, be promoted to, get to, reach, rise to
She joined the navy, where she rose to the rank of captain.

have, hold
He held officer rank in the air force for many years.

assign sb, award sb
He was assigned the rank of Commander.

be stripped of
He was stripped of his rank by a military court.

above a/the rank
He never rose above the rank of lieutenant.

below a/the rank
police officers below the rank of sergeant

in rank
He is higher in rank than I am.

rank in
all ranks in society

rank of
She reached the rank of captain.

of high, low, etc. rank
officers of senior rank

front, rear
a poet who belongs in the front rank of Latin American literature (figurative)

massed, serried (both esp. BrE)
the serried ranks of hotel staff

along a/the rank
The president moved slowly along the ranks of men.

in a/the rank
He was standing in the second rank.
The soldiers marched in three ranks of ten.

break ranks (= to leave a line of soldiers, police, etc.)
The police broke ranks and started hitting people with their batons.
He broke ranks with his fellow Republicans and opposed the war. (figurative)

close ranks (figurative)
When the establishment is attacked, it closes ranks.

rank upon rank (of sth)
Rank upon rank of caravans filled the field.

growing, swelling
These products appeal to the growing ranks of middle-class consumers.

amateur, pro (AmE), professional (all sports)
He spent two years on the college golf team before joining the professional ranks.

enter, fill, join, swell
More women are now filling the ranks of the medical profession.
Each month thousands more swell the ranks of the unemployed.

be admitted into, be admitted to
infiltrate
A CIA operative had infiltrated their ranks.

deplete, thin
Death and disease were thinning their ranks.

serve in
They had served in the ranks of the army.

climb, come up from, come up through, rise from, rise through
He came up through the ranks to become a general.

among the ranks of, within the ranks of
There is much disaffection among the ranks of the party.

beyond the ranks, outside the ranks
The group has little influence over those outside its own ranks.

in the ranks
There are few women in the highest ranks of the organization.

the rank and file
Communication worked well at management level, but didn't always make it down to the rank and file.