HackerVoca

sterile : barren, unproductive, fruitless
stern : firm, strict, adamant /adjective formal
determined not to change your opinion, decision, etc: We tried to negotiate, but they were adamant. | adamant that: Melinda was adamant that she would not travel with us.
adamantly adverb , unrelenting, uncompromising, severe, harsh, hard, infallible
stick : adhere, cohere, cling, cleave, hold
stiff : rigid, solid
stifle /'/ verb [transitive]

1 [intransitive, transitive] to stop someone from breathing or be unable to breathe comfortably, especially because the air is too hot or not fresh: He was almost stifled by the fumes.

2 [transitive] to stop something from happening or developing: rules and regulations that stifle initiative

3 [transitive] to stop a feeling from being expressed: He stifled an urge to hit her. | stifle a yawn/smile/laughter etc: Nancy stifled a yawn as the teacher's voice droned on.

: smother / / verb

1 [transitive always + adv/prep] smother sth with/in to cover the whole surface of something with something else : smother sth with/in: a delicious sponge cake smothered in chocolate | He smothered her with kisses.

2 smother your anger/irritation to hide your feelings: struggling to smother her jealousy

3 smother sb with love/kindness etc to express your feelings for someone too strongly, so that your relationship with them cannot develop normally

4 [transitive] to kill someone by putting something over their face to stop them breathing: One night she took a pillow and smothered him.

5 [transitive] to make a fire stop burning by preventing air from reaching it

6 [transitive] to get rid of anyone who opposes you: They ruthlessly smother all opposition.

, suffocate / / verb

1 [intransitive, transitive] to die or make someone die by preventing them from breathing: She rolled onto her baby and actually suffocated it!

2 be suffocating to feel uncomfortable because there is not enough fresh air: Can you open a window? I'm suffocating.

3 [transitive] to prevent a relationship, plan, business etc from developing well or being successful: Jealousy can suffocate any relationship.

suffocation / / noun [uncountable] , strangle, choke