| Word | Definitions | Synonyms |
|---|---|---|
| spontaneously | (adverb) in a spontaneous manner | - |
| (adverb) without advance preparation | Synonyms: ad lib, ad libitum, impromptu | |
| spookily | (adverb) in an unnatural eery manner | Synonyms: eerily |
| sporadically | (adverb) in a sporadic manner | Synonyms: periodically |
| sportingly | (adverb) so as to be sporting; in a sporting manner | - |
| sportively | (adverb) in a merry sportive manner | - |
| spotlessly | (adverb) in a spotless manner | - |