mullion Arch.
(ˈmʌljən)
Also 6 Sc. mullen.
[Prob. a metathetic alteration of the synonymous muniall monial. Cf. munnion, which appears somewhat later in our quots.]
1. a. A vertical bar dividing the lights in a window, esp. in Gothic architecture; also, a similar bar in screen-work.
| 1567 Harman Caveat (1869) 39 The windowes be thicke of mullions, that ther is no kreping in betwene. 1590 in Compt Bk. D. Wedderburne (S.H.S.) 64 Item for mending the Mullenis in the sylling xvj{supd}. 1793 Smeaton Edystone L. Introd. 4 The lantern..was..domed over; the doming being supported upon eight stone pillars or mullions, with openings between them for the passage of the light. a 1878 Sir G. G. Scott Lect. Archit. (1879) I. 163 This is, in fact, the great use of the mullion, to enable you to use wider windows. |
b. attrib. and Comb.: mullion seat (see quot.); mullion window = mullioned window.
| 1843 Lytton Last Bar. ii. iii, A large mullion window. 1888 C. C. Hodges Hexham Abbey 30 note, A reprise or reprisal in the foot of a window mullion or jamb... Mullionseat is the term used in some localities. |
2. Geol. Each of a series of ribs or columns of rock (spec. those composed of the local rock) on a rock face, usu. formed by folding. So mullion structure.
| 1891 E. Hull et al. Explanatory Mem. Sheets 3–5, 9–11, 15 & 16 Maps Geol. Survey Ireland iv. 53 To the north of Carnteena, quartzite of the yellowish-white compact variety, forms the bare rocky hills of Crocknaglogh and Croaghnacreggy and in some parts ‘mullion structure’ was observed—a peculiar fluting due to the shearing of the rocks. 1937 Q. Jrnl. Geol. Soc. XCIII. 597 The individual mullions are not always due to the presence of small folds, as is apparently true of the quartz rods of Beinn Thutaig. 1953 Proc. Geologists' Assoc. LXIV. 118 Distinction is drawn between mullions which look like ‘clustered columns’ and are composed of the local country-rock, and rodding. Ibid. 124 A remarkable lone mullion resulting from erosion of an abrupt double fold is found at Poll Cròm. 1963 E. S. Hills Elem. Struct. Geol. x. 310 The subdivision of a bed, more particularly a sandstone inter⁓bedded with slate, into long parallel slabs with smooth rounded surfaces is known as mullion-structure. 1966 E. H. T. Whitten Struct. Geol. Folded Rocks ix. 313 Excellent mullions developed in these quartzites, and in the granite close to the northwestern contact zone. |