Be-

The prefix be- has a long history, predating English itself. (It is found in several Old Germanic languages, including Teutonic and Gothic.) It was originally a preposition/adverb with the general sense of 'about'. It is used in constructing many modern English words: prepositions, adverbs, and verbs with participial adjectives. The meanings that it generates are many, but can be grouped, as they are in OED.

• In prepositions and adverbs, the meaning of 'about' is in its sense of 'approximate place'. Some examples are 'before' (~ 'near the front': see fore), 'beside', 'beyond', 'behind', 'between' and 'beneath', etc.
• In verbs, with their related (and sometimes independent participial adjectives), be- can be used with several different senses, still based on 'about' but usually less to do with place.
  • Be- may mean 'about' in its more general senses, as in 'to become' (~ 'to come about' or 'to occur [in a developmental sense]'). Befall means "to fall, or happen, [usually in a bad sense] as an accident". One meaning of bethink was 'to think about'.
  • When it is used with a sense of place, the meaning is 'around', as in 'beset', ~ 'surround[ed]' (if used at all in Present-day English, beset is usually used as the past forms): "she was beset by fears/enemies/seductive sights".
  • This may be 'all around', or 'thoroughly', as in 'bespattered' ('splashed all over [with]'), 'bestrewn' (usually participial) 'spread all over with',
  • The sense of 'thorough' can become a mere intensifier, as in 'to begrudge' (~ 'to resent' or 'grumble about', from a Middle English verb grucchen ~ 'to murmur') and 'to befuddle' (~ 'to make drunk, intoxicate', where the original verb 'to fuddle' meant more simply 'to drink'). Sometimes the 'intensification' can be swallowed up in remote history: it is hard to perceive believe as an intensified form of an Old Germanic root eléfan meaning 'to hold dear or pleasing', the root, too, of 'to love'; or begin is built from an Old English element ginnan, meaning 'to open'.
  • Sometimes - mostly in older English - the effect of be- is to make an intransitive verb a transitive one. One who bemoans another is grieving for that person, or that cruel fate. The reflexive verb bethink is not uncommon in Early Modern English, where a character in a play may "bethink himself of" a matter: Shakespeare writes in Measure for Measure "I have bethought me of another fault" (V i 453).
  • It can also be used to make verbs from adjectives or nouns, with the sense of 'to make [something] take the nature of the original word': bedim ('make dim') and befoul ('make foul') are examples from adjectives, bedoctor ('to admit a candidate to the degree of doctor') and besot ('to turn into a drunkard', or 'to intoxicate') from nouns.
  • Sometimes this meaning is less 'to make [someone] of the nature of [the noun or adjective]' as 'to call someone (often satirically) by the title belonging to the noun. Fielding, for example, wrote in 1743 Jonathan Wild (1743; II iii): "She beknaved, berascalled, berogued the unhappy hero" - in other words, the woman has addressed insults to the hero.
  • In general, the prefix be- can be used with another word to make a verb meaning 'to affect in a way suggested by the other word'. A traveller may be 'benighted', that is 'caught by the arrival of darkness before the destination is reached'; figuratively the "benighted heathen" were those people who had not yet 'seen the light' of (or 'been converted to') the Christian revelation. A man (and a few women) may be bewhiskered, or 'adorned with whiskers'. 'To beguile' people is 'to deceive them', formerly mostly in a bad sense (by guile, or wiles); nowadays it more commonly means 'to attract', 'to catch the attention of', most commonly "to charm, divert, amuse; to wile (one) on, or into any course" (OED, meaning 4 . 'To bewitch' is originally 'to put under a magic spell' in a very bad sense; now, as OED says (meaning 2.) "fig[urative]. To influence in a way similar to witchcraft; to fascinate, charm, enchant. Formerly often in a bad sense; but now generally said of pleasing influences". (Cf the repetition in the song 'Bewitched': "Bewitched, Bothered and Bewildered" (from the 1940 Rodgers and Hart musical Pal Joey (1940).)
  • Occasionally the way in which a person 'is affected' by a 'be-' verb is by deprivation: beheading is the most literal form of capital punishment; and a widower has been bereaved ('deprived': the Old English réafian means 'to rob', or 'to despoil') of a wife, by death.

Some words which start with be- do not begin with the prefix but the verb 'to be', in imperative form: "begone", a common command in Shakespeare's works, means 'Be [in the state where you have] gone!'. It is not unlike the more modern "Be off!" Beware! means 'Be on your guard!', 'Be cautious!', 'Be wary!'