unit of measure, Old English eln, originally "forearm, length of the arm" (as a measure, anywhere from a foot and a half to two feet), from PIE root *el- "elbow, forearm." The exact distance varied, in part depending on whose arm was used as the base and whether it was measured from the shoulder to the fingertip or the wrist: the Scottish ell was 37.2 inches, the Flemish 27 inches. Latin ulna also was a unit of linear measure, and compare cubit. The modern English unit of 45 inches seems to have been set in Tudor times.

Whereas shee tooke an inche of liberty before, tooke an ell afterwardes [Humfrey Gifford, "A Posie of Gilloflowers," 1580].

"rod or pole on which a bird alights and rests," late 13c., originally only "a pole, rod, stick, stake," from Old French perche "unit of linear measurement" (5.5 yards), also "measuring rod, pole, bar" used to measure this length (13c.), from Latin pertica "pole, long staff, measuring rod," which is related to Oscan perek "pole," Umbrian perkaf "twigs, rods." Meaning "a bar fixed horizontally for a hawk or tame bird to rest on" is attested from late 14c.; this led to the general sense of "any thing that any bird alights or rests on" (late 15c.). Figurative sense of "an elevated or secure position" is recorded from 1520s.

Middle English rod, rodde, "a stick of wood," especially a straight cutting from a woody plant, stripped of twigs, and having a particular purpose" (walking stick, wand of office, instrument of punishment), from Old English rodd "a rod, pole," which is probably cognate with Old Norse rudda "club," from Proto-Germanic *rudd- "stick, club," from PIE *reudh- "to clear land." Other sources formerly consider it to correspond to the continental words under rood.

As a long, tapering elastic pole for fishing, from mid-15c. Figurative sense of "offshoot" (mid-15c.) led to Biblical meaning "scion, tribe." As an instrument of punishment, attested from mid-12c.; also used figuratively for "any sort of correction or punishment" (14c.). In mechanics, "any bar slender in proportion to its length" (1728).

As a unit of linear measure (5½ yards or 16½ feet, also called perch or pole) attested from late 14c., from the pole used to mark it off. As a measure of land area, "a square perch," from late 14c., the usual measure in brickwork. Meaning "light-sensitive cell in a retina" is by 1837, so-called for their shape. Slang meaning "penis" is recorded from 1902; that of "handgun, pistol, revolver" is by 1903.

also yardarm, "long spar tapered at both ends and lashed to the mast of a ship from which certain sails are suspended," late 15c., from yard (n.2) in the nautical sense + arm (n.1). In 19c. British naval custom, it was permissible to begin drinking when the sun was over the yard-arm.

"workshop," especially the workroom or studio of a sculptor or painter, 1840, from French atelier "workshop," from Old French astelier "(carpenter's) workshop, woodpile" (14c.), from astele "piece of wood, a shaving, splinter," which is probably from Late Latin hastella "a thin stick," diminutive of hasta "spear, shaft" (see yard (n.2)).

also back-yard, "plot of ground at the rear of a house," 1650s (perhaps early 15c.), from back (adj.) + yard (n.1).

also barn-yard, 1510s, from barn + yard (n.1). Figurative of coarse or uncivilized behavior from 1920.

The very speeches in which Jefferson and Lincoln spoke of their hope for the future are incomprehensible to most of the voters of that future, since the vocabulary and syntax of the speeches are more difficult—more obscure—than anything the voters have read or heard. For when you defeat me in an election simply because you were, as I was not, born and bred in a log cabin, it is only a question of time until you are beaten by someone whom the pigs brought up out in the yard. The truth that all men are politically equal, the recognition of the injustice of fictitious differences, becomes a belief in the fictitiousness of differences, a conviction that it is reaction or snobbishness or Fascism to believe that any individual differences of real importance can exist. [Randall Jarrell, "The Obscurity of Poetry," 1953]

also bone-yard, "a knacker's yard, grounds around a slaughtering house," 1835, from bone (n.) + yard (n.1). Also, colloquially, "a cemetery."

also brick-yard, "open place where bricks are made," 1807, from brick (n.) + yard (n.1).

"ground adjoining a church," especially if used for burial, late Old English, from church (n.) + yard (n.1).