beady (adj.)

mid-14c., bede, "prayer bead," from Old English gebed "prayer," with intensive or collective prefix *ge- + Proto-Germanic *bidam "entreaty." This reconstructed word is also the source of Middle Dutch bede, Old High German beta, German bitte, Gothic bida "prayer, request," which according to Watkins is from a PIE root *gwhedh- "to ask, pray."

The shift in meaning in English comes via rosary beads threaded on a string to count prayers, and in verbal phrases bid one's beads, count one's beads, etc. The German cognate Bitte is the usual word for the conversational request "please." Compare Spanish cuentas "the beads of a rosary," from contar "to count."

The word is also related to bid (Old English biddan) and Gothic bidjan "to ask, pray." The sense in Modern English was further transferred to other small globular bodies, such as "drop of liquid" (1590s), "small knob forming front sight of a gun" (1831, Kentucky slang); hence draw a bead on "take aim at," 1841, U.S. colloquial.

adjective suffix, "full of or characterized by," from Old English -ig, from Proto-Germanic *-iga- (source also of Dutch, Danish, German -ig, Gothic -egs), from PIE -(i)ko-, adjectival suffix, cognate with elements in Greek -ikos, Latin -icus (see -ic). Originally added to nouns in Old English; used from 13c. with verbs, and by 15c. even with other adjectives (for example crispy). Adjectives such as hugy, vasty are artificial words that exist for the sake of poetical metrics.