"elongated, having one principal axis considerably longer than the others," early 15c., from Latin oblongus "more long than broad," originally "somewhat long," from ob "in front of; towards" here perhaps intensive (see ob-) + longus "long" (see long (adj.)). As a noun, "an oblong figure," from c. 1600.
obliquity
obliterate
obliteration
oblivion
oblivious
oblong
obloquy
obmutescence
obnoxious
obnubilate
obnubilation