Origin: 1350–1400; ME
observen < MF
observer < L
observāre to watch, regard, attend to, equiv. to
ob- ob- +
servāre to keep, save, pay heed to

Related forms: ob⋅serv⋅ing⋅ly, adverb
Synonyms:
2. note. Observe, witness imply paying strict attention to what one sees or perceives. Both are “continuative” in action. To observe is to mark or be attentive to something seen, heard, etc.; to consider carefully; to watch steadily: to observe the behavior of birds, a person's pronunciation. To witness, formerly to be present when something was happening, has added the idea of having observed with sufficient care to be able to give an account as evidence: to witness an accident. 4. mention, say. 6. follow, fulfill. 7. celebrate, keep.
Antonyms:
1–3, 6–8. ignore.