Synonyms of the word 
OBSERVED → ASCERTAINED - DETERMINED - DISCOVERED
observed
- v. simple past tense and past participle of observe.
ascertained
- v. simple past tense and past participle of ascertain.
determined
- adj. Decided; resolute, possessing much determination.
- v. simple past tense and past participle of determine.
discovered
- v. simple past tense and past participle of discover.
If you are interested in words, visit the following sites :
- wiktionary.org/observed For complete definition of a word
- 1word.ws/observed to play with words, suffixs, prefixs, etc.