para-1

1.
a prefix appearing in loanwords from Greek, most often attached to verbs and verbal derivatives, with the meanings “at or to one side of, beside, side by side” (parabola; paragraph; parallel; paralysis), “beyond, past, by” (paradox; paragogue); by extension from these senses, this prefix came to designate objects or activities auxiliary to or derivative of that denoted by the base word (parody; paronomasia), and hence abnormal or defective (paranoia), a sense now common in modern scientific coinages (parageusia; paralexia). As an English prefix, para-1, may have any of these senses; it is also productive in the naming of occupational roles considered ancillary or subsidiary to roles requiring more training, or of a higher status, on such models as paramedical, and paraprofessional: paralegal; paralibrarian; parapolice .
2.
Chemistry. a combining form designating the para (1, 4) position in the benzene ring.
Abbreviation: p-.
Compare meta- (def 2c), ortho- (def 2b).
Also, especially before a vowel, par-.
Origin
< Greek para-, combining form representing pará (preposition) beside, alongside of, by, beyond

para-2

1.
a combining form meaning “guard against,” occurring in loanwords from French, or, via French, from Italian: parachute; parasol .
Origin
< French < Italian para, 3rd singular present of parare to prepare against, ward off < Latin parāre to prepare

para-3

1.
a combining form extracted from parachute, forming compounds denoting persons or things utilizing parachutes or landed by parachute: paradrop; paradoctor; paraglider; paratrooper .
British Dictionary definitions for para-

para-1

prefix
1.
beside; near: parameter, parathyroid
2.
beyond: parapsychology
3.
resembling: paramnesia
4.
defective; abnormal: paraesthesia
5.
subsidiary to: paraphysis
6.
(usually in italics) denoting that an organic compound contains a benzene ring with substituents attached to atoms that are directly opposite across the ring (the 1,4- positions): paradinitrobenzene, para-cresol, p- Compare ortho- (sense 4), meta- (sense 4)
7.
denoting an isomer, polymer, or compound related to a specified compound: paraldehyde, paracasein
8.
denoting the form of a diatomic substance in which the spins of the two constituent atoms are antiparallel: parahydrogen Compare ortho- (sense 6)
Word Origin
from Greek para (prep) alongside, beyond

para-2

combining form
1.
indicating an object that acts as a protection against something: parachute, parasol
Word Origin
via French from Italian para-, from parare to defend, shield against, ultimately from Latin parāre to prepare
Word Origin and History for para-

before vowels, par-, word-forming element meaning "alongside, beyond; altered; contrary; irregular, abnormal," from Greek para- from para (prep.) "beside, near, issuing from, against, contrary to," from PIE *prea, from root *per- (1) "forward, through" (see per). Cognate with Old English for- "off, away."

word-forming element meaning "defense, protection against; that which protects from," from Italian para, imperative of parare "to ward off," from Latin parare "make ready" (see pare).

para- in Medicine

para- or par-
pref.

  1. Beside; near; alongside: paranucleus.

  2. Beyond: parapsychology.

  3. Incorrect; abnormal: paradipsia.

  4. Similar to; resembling: paratyphoid.

  5. Subsidiary; assistant: paramedical.

  6. Isomeric; polymeric: paraldehyde.

  7. A diatomic molecule in which the nuclei have opposite spin directions: parahydrogen.


  8. Abbr. p- Of or relating to one of three possible isomers of a benzene ring with two attached chemical groups in which the carbon atoms with attached groups are separated by two unsubstituted carbon atoms. Usually in italic: para-bromoiodobenzene.