gorge; ravine; canyon; glen
maze; labyrinth; inner ear
valley; ravine; cleavage (breasts); slum
divergence; ramification; bifurcation; branching off
undulation; ups and downs; highs and lows
pause; suspension; rest; stoppage
competing companies; rival companies
flexibility; pliability; softness; elasticity
base; basis; base (e.g. military); depot; base; base bag
downward compatible; backward compatible; compatible with input or components intended for lower tier or older systems, versions, etc.; upward compatible; forward compatible; compatible with input or components intended for higher tier or later systems, versions, etc.
breastplate; chest protector; bib
plate (often as in "tectonic plate")
both in name and reality; both in name and substance
highest peak; highest mountain; greatest authority; most prominent person; pinnacle (e.g. of art)
clearing one's throat; cough
conversion; diversion; changeover; commutation; switchover
round shape; circle; circular form
athletic meet (esp. at school); sports day
several times; several degrees
place of execution; execution site
to choke; to have trouble breathing
diagonally upward; (going in a) completely unexpected direction (of a story, result, etc.)
class society; class-based society; hierarchical society
physical culture; bodybuilding (body development, not necessarily weightlifting)
geometric progression; proliferation; multiplying like rats
to be the ruin of (a person)
staringly; scrutinizing; scrutinising
meddling; meddlesomeness; nosiness; interference; officiousness
belligerence; fighting spirit
false impression; deceptive appearance; mere show
sweeping with fire; mowing down; strafing
advantageous; favourable; better; profitable; lucrative; gainful
after all; in the end; when all's said and done; for the time being; at present
general; admiral; head; chief; old chap; mate
staff officer; military staff; adviser; counselor; counsellor