SIMULTANEOUS, SIMULTANEOUSLY
ADJECTIVES
1400 ► ALTOGETHER existing at the same time; simultaneous; immediate → obs.
1654 ► SIMULTAL simultaneous → obs.
1669 ► SYNCHRONOUS existing or happening at the same time; ontemporary; simultaneous
1953 ► MONOCHRONOUS simultaneous, occurring at the same time
ADVERBS
1922 ► ONETIME simultaneously, at the same time → Amer. dial.
NOUNS
1660 ► SYNCHRONAL a simultaneous or contemporary event → obs.
1677 ► SIMULTY the quality of being simultaneous → obs.
1802 ► SIMULTANEITY the quality of being simultaneous; occurrence at the same time
VERBS
1687 ► JUMP IN QUILL to act simultaneously or in harmony → obs.
Lexicophilia 