Survey of English Place-Names

Historical Forms

• Is slepe, Hyslepe c.980 BCS1130 c.1200

• Islep, Slepe 1086 DB

• Islep(e) 1175 P 1316 FA

• Hystlapa 1190 P

• Ystlapa 1191 P

• Istlepe 1247 Ass

• Ystlepe 1273 Swaffham

• Islape 1205 Cur 1242 Fees

• Isalop 1205 Cur

• Isselep(e) c.1220 WellsR

• Isselep juxta Thrapston 1317 Ass

• Itheslepe c.1220 WellsR

• Itteslep' 1253 Ipm

• Hislep 1241 P

• Islip 1275 RH 1346 FA

• Eslep 1284 FA

• Iselep 1294 Ass 1331 Cl

Etymology

The second element in this name is clearly OE  slæpe, 'slippery place,' referring to the hill which slopes down sharply to the Nene. It is difficult to suggest any solution of the name if we take the initial sound to be Is -. If it is His -, as some of the earliest forms suggest, we may take it that the first element is OE  hys (s )e , 'young man, warrior,' again a word which like the beorn of Barnwell supra 178 is only found in poetic texts, but which at an early date may have been in common prose use.Hence 'slippery hill of the young men or warriors.' For other possible occurrences of this term in place-names v. Husborne Crawley (PN BedsHu 118).

Professor Ekwall would take the Is -forms to be the correct ones, and suggests that at some time in its history the Nene may have been known at this point by the name of its important tributary the Ise (v. supra 3) which joins it a few miles farther north. Cf. the history of Leicester (RN xlii), which probably takes its name from the tributary Legra (on which stands Leire), whose name was transferred to the main river Soar on which Leicester itself stands. In that case the name would mean 'slippery bank of the Ise river.'