Other forms: reclining, reclined, reclines
To recline is to tilt a seat backwards. Recline the seat, fully reclined, recline your chair.
On a plane it is a small war: the space belongs to the person in front by design and to the person behind in practice, and there is no settled etiquette. Reclining also means lying back generally. Note incline and decline, from the same Latin verb meaning to lean.
1verbreclineTo tilt a seat backwards.
“Would you mind if I reclined my seat a little?”
recline is a leaning back.
Latin reclinare is re plus clinare, to lean. Incline, decline and climate come from the same leaning.
Proto-Indo-European
*ḱley-
Latin
reclino — to bend back
English, today
recline
Borrowed from Latin reclino (“to bend back”). Compare decline, incline.
Etymology from Wiktionary, CC BY-SA