allowed to drop or fall. / (of a phone call) suddenly disconnected.

simple past tense and past participle of drop in

present participle of drop in

The action of one who drops in.

present participle of drop by

simple past tense and past participle of drop by

An impermeable sheet of material meant to catch paint or other hard-to-clean substances.

(US) A letter mailed at a post office and either kept for general delivery, or delivered to a post office box, at that same post office.

(informal, idiomatic) Without any hesitation; instantly.

Understanding is reached; one comprehends.