OPINION OF THE COURT
Harvey, J. Plaintiff, a physician licensed to practice in New York, is a radiologist with a subspecialty in sonography, also known as ultrasound. Plaintiff was, during all relevant times, a Medicaid provider who performed and billed Medicaid for sonographic examinations performed on Medicaid recipients. Among those billings were ones for consecutive sonograms on one or more patients during a single visit and, in each case, plaintiff billed each sonogram at the full amount set forth in the Medicaid Management Information System (hereinafter MMIS) reimbursement fee schedule.
In April 1988 defendant informed plaintiff that, after reviewing the claims submitted by plaintiff in 1986 and 1987, its analysis showed that plaintiff allegedly improperly failed to use the MMIS modifier "-62” described in the MMIS Provider Manual when submitting claims for multiple sonograms performed during a single visit. At the relevant time, the MMIS manual’s definition of the -62 modifier read as follows: "Multiple X-Ray Exams: When more than one x-ray exam is performed during the same visit, use the usual fee code for the primary procedure and identify the secondary procedure(s) by adding the modifier '-62’ to the procedure number(s). (Reimbursement will not exceed 60% of the maximum State Medical Fee Schedule amount.)”1 According to defendant, the term "x-ray” in the MMIS -62 modifier was meant to refer to all radiological procedures, including the sonograms performed by plaintiff. Accordingly, defendant demanded that plaintiff repay $265,748 of alleged overpayments for procedures where the -62 modifier allegedly should have been applied but was not.
Plaintiff disputed defendant’s conclusion that he improperly failed to use the -62 modifier. The parties agreed that plaintiff would bring a declaratory judgment action upon a stipulated set of facts to decide the -62 modifier issue. Following joinder *14of issue, plaintiff moved for summary judgment seeking a declaration that the -62 modifier did not apply to multiple sonograms performed during single visits in 1986 and 1987. Defendant cross-moved for summary judgment but Supreme Court found in favor of plaintiff. A judgment was entered in plaintiff’s favor granting the requested declaratory relief and held that defendant’s claim for reimbursement in the amount of $265,748 was void. Defendant now appeals.
As acknowledged by the parties, the first sentence in the MMIS manual for radiology under the heading "General Information and Rules” states that "[tjhese rules apply to all procedure codes found in the Radiology Section of this Fee Schedule including * * * ultrasound * * * procedures”. Rule 3 of the General Information and Rules states that when "multiple x-ray examinations are performed during the same visit”, the MMIS -62 modifier must be used in billing Medicaid. As noted previously, the definition of the -62 modifier contained in the rules also makes reference to billing fee codes when multiple X rays are performed during the same visit. Based on this wording, defendant argues that it is reasonable to conclude that because the first sentence of the general rule states that the rules apply to all radiological procedures, the term "x-ray” must include ultrasound or sonograms. Moreover, defendant argues that because the MMIS -62 modifier is a part of the regulations which it enforces, its interpretation of the term "x-ray” in that modifier should be accorded substantial deference.
We cannot agree with defendant’s arguments. With respect to the threshold issue of whether defendant’s interpretation is entitled to judicial deference, we note that the term "x-ray” in the -62 modifier is not a technical term within defendant’s area of expertise. Accordingly, this court is not required to give special deference to defendant’s interpretation of the term (see, Matter of De Mayo v Rensselaer Polytech Inst., 74 NY2d 459, 462; Kurcsics v Merchants Mut. Ins. Co., 49 NY2d 451, 459; Matter of Judd v Constantine, 153 AD2d 270, 272). As a result, we look instead to the well-settled rule of construction that words of common usage should be given their ordinary meaning unless it is clear that a different meaning was intended (see, Catlin v Sobol, 77 NY2d 552, 559; We’re Assocs. Co. v Cohen, Stracher & Bloom, 65 NY2d 148, 151; Matter of Cabrini Med. Center v Axelrod, 116 AD2d 834, 836; cf., McKinney’s Cons Laws of NY, Book 1, Statutes § 94).
Here, the terms "x-ray” and "sonogram” are, among the physicians to whom the MMIS fee schedules apply if not also among lay persons, commonly understood to mean two differ*15ent procedures.2 Moreover, despite defendant’s contention that the term "x-ray” really means all radiological services, it is significant that the language in defendant’s definition of the MMIS -60 and -61 modifiers during the relevant period refers specifically to "radiological services” and does not simply state "x-rays”. It therefore becomes apparent that the general phrase "radiological services”, and not "x-rays”, was meant to refer to all the radiological procedures named in the first sentence of the manual under "General Information and Rules”, which explains why this general phrase is then repeated in two of the modifiers. This is confirmed by the use of the specific term "x-ray” in the -62 modifier, which then created an inference that the other procedures not named, such as sonograms or ultrasound, were intentionally omitted (cf., McKinney’s Cons Laws of NY, Book 1, Statutes § 240). Accordingly, in the absence of proof that the term "x-ray” was meant to have any meaning other than its ordinary meaning, we find no basis for disturbing Supreme Court’s determination.
. We note that the MMIS modifiers are set forth in defendant’s regulations (see, 18 NYCRR 533.6 [e]) and the MMIS -62 modifier employs the term "radiology procedure” instead of "x-ray exam”. However, since this change was made after the time relevant to this appeal, interpretation of the latter term is the sole subject of this appeal.
. The dictionary defines the term "x-ray” as "a nonluminous electromagnetic ray or radiation of extremely short wavelength * * * capable of penetrating opaque or solid substances, ionizing gases and body tissues through which they pass or, by extended exposure, destroying tissue, and affecting photographic plates and fluorescent screens” (Webster’s New World Dictionary of the American Language 1644 [20th college ed]). "Ultrasound” is defined as "the application of ultrasonic waves to therapy or diagnostics, as in deep-heat treatment of a joint or imaging of internal structures” (Random House Dictionary of the English Language 2050-2051 [unabridged 2d ed 1987]). A "sonogram” is "the visual image produced by reflected sound waves in a diagnostic ultrasound examination” (id., at 1820).