In Arabic we find عصر עצר with the meaning of “press together”, and also عضر עצר in the sense of “spoke out, blessed”, both befitting the Hebrew עצרת. I also found فعم פעם meaning “be full, be fat, be plump, be well rounded, be inflated”. From this we learn that surely פעם is the fleshy part of the leg, possibly the heel, may be the thigh (i. e. the thick part). I think that פעמון is also just a bulb. I understand it in Shmot that פעמונים were little golden balls attached by string to produce a tinkling sound upon striking each other. You say that some people claim that the earlier meaning of פעם was "to strike, to beat". I can’t see the basis for this claim, where did they get it? The book of Shmot mentions also רימון but this may refer to the tree, as is תפוח, rather than the fruit. Sorry, but I did not find any good Arabic cognate to ר'מ'ן.
Kobi
The word عصر עצר in Arabic also means a time between noon and sunset when the third Muslim daily prayer is offered. ِAfter reading this post I am inclined to think that عصر came from a related word that is closer to Atzeret which is عصرية which has religious connotations. When a person dies, people come to the family of the deceased to offer condolences at the time of عصر. This gathering is called عصرية, Hence I think عصرية (may be from atzeret) gave the name of عصر to the time of this gathering. I think the meaning that Kobe found (to squeeze) is an unrelated meaning to the same word.
Kobe: רימון or Rumman (resh-stressed mim-aleph-noon) is pomegranate in Arabic, but I am not sure if this is relevant to what you are saying, sorry.
Stahl writes that the Arabic asara, meaning "to press, squeeze" is related to the Hebrew עצר - which has the same meaning. A מעצרת is an olive press. Klein says that the עצר meaning "to press" and the עצר meaning "to restrain" may be related.
Stahl provides more terms in Arabic related to the same root. Asar is a term for autumn - when the grapes are pressed into wine. From here, someone who has reached the autumn of their lives, the end of their days is also considered to be in the period of asar. The period parallel to autumn in the day is the afternoon - aser.
As far as פעם meaning "to beat" - it has that meaning almost every time it appears as a verb in the Bible.
Thanks Dave, may be I should add that عصرية is probably a Syrian term.
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