A is the first word in our English dictionary
AN is definitely an indefinite article
ANE is one in Scotland
OR
LAN is your local area network
Either way
PLAN is what you do to amuse the Gods
PLANE is an unfancy flat surface
PLANET is a nearly spherical sun orbiter
PLANETS are what we now have eight of since Pluto\'s demotion date
(which was 2 0 0 8)
or SPLANET is what you do to Lucy
or ESPLANET is what Ricky does very slowly.