I have an English background too. Well, as English as Singapore can give me. :p
I think the word you are looking for is "Throng". I too, often came across this word, mostly when reading fiction when I was very young (before 12 years old). I don't think I've met a person who used this verb. You say your grandfather used it? Who did he threaten to throng?
I copied this off the OED.
throng, v.
1. trans. To press or compress violently; to squeeze, crush. Obs. 2. intr. To push or force one's way, as through a crowd or against obstacles; to press. Obs.
3. a. intr. To assemble in a group or crowd; to collect in large numbers; to crowd; also, to go in a crowd.
b. indirect pass. (cf. 4). Obs.
4. trans. To crowd round and press upon; to press upon as in a crowd, to jostle. Also fig.
5. To bring or drive into a crowd, or into one place; to collect closely, to crowd; to press or drive in a crowd (quot. 1615). Chiefly in pa. pple.
6. a. To fill or occupy (a place, etc.) with a large number of things or persons, or quantity of something; to crowd, cram, stuff; to burden (quot. 1648).
b. Said of a multitude of persons or things: To occupy completely, fill, crowd (a place, etc.).
c. pa. pple. Occupied by a crowd or multitude of persons or things; crowded, crammed, filled (const. with, or absol.). See also THRONGED 2.
d. intr. for pass. Now dial.
Definition 1 is probably the one you are looking for. "trans." stands for "transitive", whatever that means. "Obs." stands for "obsolete"
Hope this helps.
metwin1
