affectionately; with favourable disposition; in a kindly or loving manner; fondly ...1779
shortened from affectionately (adv.)
FIRST DOCUMENTED USE
1779 - see EXAMPLE below
"...I pity the Lady and Children exceedingly, but I have no tender feelings for the old fellow on many accounts. & am Sir Yours most affly., A.B...."
From: The Papers of Thomas Jefferson, 18 June 1779 - 30 September 1780
Edited by Julian P. Boyd, 1951
To Thomas Jefferson from Cyrus Griffin, 13 July 1779