Crossword puzzle clue "something often fallen out of"

Something often fallen out of

Something that's fallen off a shelf?

Something fallen off a shelf?

Fallen seed, often

Open an innings and be not out after all other wickets have fallen

Something often seen on a street corner, briefly ... or, literally, something seen in each corner of this puzzle

Figure something out, especially something obvious

Eckhart of "Olympus Has Fallen"