1. tacit
( adj. ) – implied, not stated outright; understood without being openly expressed
Examples:
Management has given its tacit approval to the plan.
Synonyms:
unspoken, implicit, inferred, unexpressed, unsaid;
silent, quiet
Antonyms:
Bold, explicit, clear

2. tactful (adj.) – saying or doing the proper thing Examples:
The counselor approached the student in a tactful manner.
Synonyms:
Diplomatic, polite, thoughtful. Considerate, judicious
Antonyms:
Tactless, careless, indiscreet, inconsiderate

3. Spoil, dirty, infect, disease, defile, to infect, corrupt
taint
(verb) – to affect with something harmful; contaminate
Examples:
His behavior was tainted by the influence of the new student in class. Now they both are in ISS.
Synonyms:
Spoil, dirty, infect, disease, defile, to infect, corrupt
Antonyms:
Purify, clean

4. Narrow, shrink, diminish, wane Increase, augment, boost
taper off
(verb) – gradually decrease, grow smaller at one end; dwindle
Examples:
The storm is beginning to taper off now.
I haven't stopped smoking entirely, but I'm tapering off to three cigarettes a day.
His interest in that girl is tapering off. I guess he got bored of chasing her.
Synonyms:
Narrow, shrink, diminish, wane
Antonyms:
Increase, augment, boost

5. moderate, mitigate, soothe, to soft down Intensify, deepen, strengthen
temper
(verb) – to moderate; to make less extreme
(n.) - heat of mind or passion, shown in outbursts of anger, resentment
Examples:
You need to temper yourself down. You cannot let your feelings run wildly.
Synonyms:
moderate, mitigate, soothe, to soft down
Antonyms:
Intensify, deepen, strengthen

6. Principle, theory, precept, doctrine
tenet
(noun) – idea or belief
Examples
Equality is the main tenet of a democracy.
Synonyms:
Principle, theory, precept, doctrine
Do not confuse with TENANT
( a person who occupies a place for a limited period of time)